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Avantron AT-2000R/RQ User Manual

1. 22 to 35 dB CCUTACY 1 5 dB Error Vector Magnitude EVM Range 1 2 to 4 1 CCUTACY 0 4 over 1 2 to 2 0 range 0 8 over 2 1 to 4 1 range Average Bit Error Rate BER Before R S Decoding RANge 1 0 x 10 to 1 0 x 10 User selectable Time Period 1 to 60 minutes Estimated Average Bit Error Rate BER After R S Decoding User selectable Time Period 1 to 60 minutes Estimated Noise Margin Range 1 to 12 dB CCUTACY 1 5 dB Data Logging User selectable Time Period 1 to 60 minutes Errored Seconds Severely Errored Seconds Symbol Rate Range 5 057 to 5 360 Msymb s Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 12 Available Options for 2000 Series AT2CATVPAK AT2SWPFW RBAS1 AT2VIDOUT AT2HCBAT AT2NETR AT2CAL3YR AT2W EXT R AT 2000G AT BAS 1
2. 0 75 dB 5 1000 MHz Sensitivity 65 dBmV to 65 dBmV Level accuracy 0 75 dB 25 C Level resolution 0 1 dB Impedance at RF input 75 ohm Input Return Loss gt 16 dB gt 10 dB attenuation Maximum safe input 68 dBmV Noise figure 10 dB max 0 dB attenuation Spurious free dynamic range gt 70 dB Vertical scale 10 5 2 dB Division Input attenuator 0 65 dB in 5 GB steps Internal calibrator 38 5 MHz 5 dBmV Temperature Readout Range 40 C to 100 C 1 5 C Display type TFT Active Matrix Color LCD Display size 162 5 mm 6 4 inches POWER Battery type
3. Rechargeable lead acid 12 Volt 5 Ah Charger Type Battery Charger 12 Volt 2 A Charge Time Approx 3 hours Operating Time Approx 2 5 hours Temperature range Operating 0 C to 50 C Non operating 20 C to 55 C Size 304 8mm x 177 8mm x 355 6mm 12 W x 7 H x 14 D Weight w battery 8 6 Kg 19 6 pounds Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary CATV Measurement Specifications Channel Selection Frequency Channel Video or Channel Audio Channel Plans 4 custom plans NTSC PAL or other Maximum of 250 positions Tuning Range 1 MHz to 1 GHz TV Channel amplitude range 40 dBmV to 65 dBmV 0 75dB for S N gt 30dB TV Visual Frequency ACCULACY Carrier Frequ
4. Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 48 Resolution Bandwidth RBW F3 RBW When analysing signals ATT 15 dB UBW A 18 kHz SWT A 308ms RBW M 16 kHz S a spectrum analyzer sl a i un MHz Se Ge SS deh MHz SPAN traces out the shape of enu T E 4 SS 5 4 FH Lu ZERO 5 the analyzers Soe intermediate IF filters IW j A aes ee As we change the filter EZ i bandwidth we change the width of the 25 displayed response Signal resolution is ENEE A Oe determined by the IF Logg pair anomia filters inside the Aldo ica AR H BI i spectrum analyzer The wider a filter is the wider the signal appears on the screen One way to determine if the RBW filter is wide enough to respond fully to the input signal is to increase the filter and watch until the amplitude no longer increases The RBW and VBW settings should be set to 300kHz and 100kHz respectfully or wider if spans wider than 10MHz are to be used It is preferable to couple sweep time and bandwidths to change automatically h RESOLUTION e A0 Zut BANDWIDTH SWEEP TIME NO AVERAGE The Resolution bandwidth RBW function selects the IF filter setting for a measurement The Model AT 2000R RQ has 4 different Resolution Bandwidth RBW settings to choose from 1MHz 300 kHz 30 kHz and 10 kHz Sweep Time SWT F4 SWEEP TIME In order to keep the spectrum analyzer calibrated sweep t
5. MAX SPAN F2 ZERO SPAN F3 RESOLUTION BANDWIDTH F4 SWEEP TIME F5 VIDEO BANDWIDTH F6 TRIGGER AMPL F1 ATTEN F2 REFERENCE LEVEL F3 VERTICAL SCALE F4 REFERENCE OFFSET MARK F1 V1 MARKER vertical marker 1 F2 V2 MARKER vertical marker 2 and dB Hz F3 H1 MARKER horizontal marker 1 F4 H2 MARKER horizontal marker 2 F5 V1 gt CF tunes vertical marker 1 at the center frequency F6 V2 gt CF tunes vertical marker 2 at the center frequency TRACE F1 NO AVERAGE averaging off F2 AVERAGE 1 fast update F3 AVERAGE 2 slow update F4 PEAK HOLD Pressing the ESC key brings up a secondary soft key menu of other modes which can be directly accessed using the same soft keys Frequency F1 CENTER FREQUENCY The FREQ abr for Frequency control key accesses the frequency tuning functions of the Model AT 2000R RQ spectrum analyzer The basic mode of tuning is by simply entering a center frequency value in MHz and pressing ENTER 4 or by using the spin knob and arrow keys The frequency tuning function is activated by default whenever accessing a mode which may require tuning spectrum analyzer single carrier etc Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 47 F2 VIDEO CARRIER F3 AUDIO CARRIER Included with the optional CATV MEASUREMENT PAK are 2 additional tuning modes which
6. 40 to 95 Resolution 0 1 CCUTACY 1 5 C N gt 40 dB Signal type Use VITS line with white reference In Channel Response Range 10 dB Resolution 0 1 dB ACCULACY 0 25 dB Signal type Use VITS line with full amplitude multiburst signal Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 10 Carrier to Noise Ratio Optimum Range O dBmV to 10 dBmV with O dB Attenuation Maximum C N 60 dB with 1 dB accuracy 65 dB with 3 dB accuracy Resolution 0 1 dB CSO CTB Optimum Range 4 dBmV to 4 dBmV with O dB Attenuation Maximum CSO CTB 64 dB with 1 5 dB accuracy 71 dB with 4 dB accuracy Resolution 0 1 dB Note C N CSO and CTB
7. display trace shows the lm Vin d actual carriers that are at i O Low RES least 35 40 dB above the asi ld ii EC reference sweep signal eee A Oe or ieee ee The FILTER display function as shown in Figure 29 uses special ee Sears pl software technique to St 7 extrapolate the sweep 7 Min OFF High trace from the channel SS signals on the system Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 86 The Avantron sweep system processes 5000 data points across 1 GHz of bandwidth This fine resolution allows Avantron to offer the unique feature of ZOOMING in to small portions of the sweep response The ZOOM can be set to as little as 10 MHz Span 1 MHz per division is sufficient for viewing in channel frequency response Two levels of digital averaging are available AVERAGE MIN o MAX The Avantron System Sweep display will show very subtle problems such as bad VSWR mismatch problems The display clearly shows the video and audio carriers on the system as well as any response problem or suckout that may appear between the carriers Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 87 Avantron Service and Support Avantron is committed to excellent service worldwide Our goal is to provide you with professional assistance in the use of our software and services wherever you are located Technical Support and Customer Servic
8. Ba fie Gidse NTSC Tiner 1 gt G00 jv ce 3 15 Vidco MISE om BOOT Om BEF 2 3 On Sisplag Switch lafermation Oa OFF n Company Identification 3 RUANTRON IMC User Idgomtification ooooooooooo 2 ROCER BATE Fermat US International kannen 5 OS DATE Entor as d mm yeyg 2 Sop 17 1999 TIME Enter 20h clock a5 hb an 55 s 3 16728758 Invalid Loy Beep BN DFF z 06f Power Shet0F Varning Beep On 0FF On Printer Type Epsoa BP Laser Epsoa Save Setup lt Keob rrows gt Liae lt Esc gt Qeit witheut saws lt Enter gt Eeit Reset Barn Defaults LCD Backlight off Timer Set LCD power down delay time in minutes Enter 999 to disable the feature The LCD power down feature conserves battery power DEFAULT VALUE IS 5 MINUTES Power off Timer Set Power off delay time in minutes Enter 999 to disable the feature The Power off feature helps conserve battery charge by powering off the Model AT 2000R RQ All active settings are saved during Power Off so that when the unit is powered on again the settings are exactly the same as when it powered off You may continue to operate the unit by pressing any key or rotating the knob in either direction thus restarting the countdown The countdown is automatically reset at any key press or knob rotation DEFAULT VALUE IS 15 MINUTES Video NTSC Output On Off Turn On or Off
9. SOFTWARE VERSION 4 18a8 Model AT 2000R RQ SERIAL NUMBER 0698 8797 Color such as Model and ew CALIBRATION SITE Avantron Inc lab Serial numbers CALIBRATION DATE Feb 94 1995 Fi Channel software version Plans FORWARD SWEEP OPTION INSTALLED calibration date and BAS OPTION INSTALLED CATU MEASUREMENT PACKAGE INSTALLED time as well as all DIGITAL CH POWER OPTION INSTALLED installed options D A k ACTIVE CHANNEL PLAN 1 NTSC Additional information includes certain user ACTIVE COLOR SELECTION CUSTOM USER 2 preferences such as the active channel plan Ar optional CATV PAK required and the active colour setting User Parameters The Model AT 2000R RQ has many user defined preferences known as PARAMETERS To change any of the parameters scroll through the menu using the spin knob when the desired parameter is highlighted press ENTER this will allow you to make the necessary changes After you have terminated simply choose from the on screen menu Save Setup F5 to store the parameters The PARAMETER screen displays information about the preferences set on the Model AT 2000R RQ such as LCD Power Down Delay and Power Off delay Beep On Off preferences as well as the type of printer driver and date format selected Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 40 C Parameters Setup 7 ouer steft nor 1 Y coooooon 5 Video MISC Ostput ONSOFF Y
10. display resolution RF same 55 24985 HHz 21 2 dBnU carrier level and Merca AUDIO 2 59 74995 MHZ 6 4 dBmU y S a 4 50010 MHz 14 8 dB frequency is as simple has tuning in the frequency or TV channel and both visual and aural levels and frequencies are continuously measured Results are displayed at the bottom of the screen showing the delta values as well Multi Carrier Mode Select MULTI CARRIER from the Main Menu screen The Multi Carrier mode pp e features simultaneous demu level measurements of 6 carrier or TV channel oo GE wm ooo VIDEO frequencies The Ea E MM mm AAN function is especially E SE useful for the accurate o e RW 9 Sa GER setting of the amplifier e D a high and low AGC pilot SE channels The 8 WW 3 a programming of the 01 8 oe m o display bars is a simple AAA procedure 55 25 145 25 211 25 295 25 391 25 439 25 MHz Ween 22 8 23 3 22 6 20 6 16 6 12 2 dBmU 2 U 18 U 13 U 36 U 52 U 60 U CENTER FREQUENCY Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 54 Once in the MULTI CARRIER mode press the FREQ key on the front panel and then either enter a frequency in megahertz F1 channel number F2 or audio carrier F3 You will notice that the bar on the left has a marker through 1t this is to indicate that it is active and ready to be programmed To switch between the display bars select from the on screen m
11. function to initialize the QAM measurement with the current settings Use F6 RESET DEFAULTS to return all setting to factory default values Step 3 The AT 2000R RQ will automatically set the instrument settings and start testing the digital signal in real time The initial test performed is attempting to lock in to the Forward Error Correction At the bottom of the screen there are 3 separate lock indicators If there is a problem the display will indicate UNLOCK in red box SYHB LOCK FEC LOCK STREAM LOCK Symbol Lock FEC Lock Stream Lock Pre and Post Bit Error Rate BER Bit Error Rate BER is a very important indicator of the health of a digital transmission BER Pre Fecj system As data is transmitted some of the bits 4 8F 85 may not arrive properly at the receiver and the more bits that are incorrect the more the signal BER Post Fec will be affected 1 8E 89 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 73 BER measurements are done after digital decoding that is after Trellis decoding De randomization De interleave but before and after Reed Solomon error correction The Error Correction mechanism detects all errors hence the Bit Error Rate Pre FEC indicates all errors found in the previous second it is displayed as a ratio to the total transmitted bits in the second But all errors cannot be corrected even if they are flagged so the Bit Error Rate Post FEC is the ratio ov
12. selecting RECALL OUTPUT LEVELS BRIDGER 19 SETTINGS F2 The CN CYB AND ESO ON HIG 10 various settings are indicated by their user defined alphanumeric designations and may be recalled simply by highlighting them with the spin knob or arrow keys and then pressing the ENTER key If Display Item F1 is pressed then only the settings parameters will be displayed Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 28 Recalling a stored setting instantly prepares the Model AT 2000R RQ with the exact same previously stored settings such as Attenuator Span Frequency etc If there are many settings or records stored using the same site ID name it won t take long before the on screen directory fills up One way to help minimise this is to select this function from the on screen menu Full Compressed Directory F2 What this does is that it displays only the first item of all identical ID s As an example 1f there were ten tests performed under one ID instead of showing all ten only the first will appear if this function is used This allows to display more of a variety of records or settings To de compress just press F2 and all will be displayed on the screen To scroll through files on screen use the spin knob for other pages use arrow keys Pg Dn 4 Pg Up Superimpose On A Live Trace The AT 2000R RQ allows a stored trace to be Recalled and superimposed on a live trace for comparing This
13. 2508 4 5008 Tag Untag for individual channels s e 2 B e Cones as 11 TU Y 11 199 2508 4 5000 12 TU Y 12 265 2568 4 5000 S To access the Channel As 1 S i 421 2600 Seen ch EN Y D D anne 15 TU Y B 127 2500 4 5000 Plans screen go to 17 mw 139 2509 15099 MAIN MENU select 19 om F 151 2509 15099 eg 26 TU Y G 157 2566 4 5000 SETUP and from the on 21 wW H 163 2588 4 5608 screen menu choose a Ger Channel Plans F3 The TEST column is used to indicate whether that position will be included in the Auto Test or not A tag is used to select the channels for the AUTOTEST levels and frequency measurements TV and FM channels selected with the Tag will be measured automatically when AUTOTEST is initiated Channel tables have the added feature of allowing a user to enter non standard frequencies such as leakage detector pilot or data carrier etc There are a number of extra slots for custom user defined frequencies To make changes in the channel line up or edit frequencies simply do the following Access the CHANNEL PLANS screen by selecting from the on screen menu Channel Plans F3 in the SET UP screen From the choice of plans select the one that is to be edited by using the spin knob to scroll through At this point if the ENTER 4J key is pressed you will not be able to edit anything but instead what you have done is simply select that Channel Plan To edit select from the on screen menu Edit Plan F1 this will bring you
14. 9 Type the command set priv which will enable you to configure the Network Interface card of the AT 2000R RQ The screen should now look like the one shown below 8 Telnet 192 0 1 200 Connexion Edition Terminal 2 3 Lantronix MSS166 Version U3 5 6 981619 Type HELP at the Local_2 gt prompt for assistance Username gt user Local_2 gt set priv Password gt EE Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 37 10 At the password prompt enter the default configuration password which is system The password will not be echoed on screen After the password will have been entered the command prompt should change from a single gt to a double gt gt as shown below Telnet 192 0 1 200 PSIe EZ Connexion Edition Terminal 2 2 Username gt user Local_2 gt set priv H Password gt Local_2 gt gt II AL 11 You are now authorised to change the Network Interface card settings Enter the command change ipaddress IP address where IP address will be the new IP Address of the AT 2000R RQ In the example below the IP Address was changed to 192 0 1 229 i Telnet 192 0 1 200 lolx Connexion Edition Terminal Username gt user Local _2 gt set priv al Password gt Local_2 gt gt change ipaddress 192 8 1 229 Info TCP users exist reboot to take effect Local_2 gt gt Jj E As noted on screen the IP address will be changed only upon rebooting the
15. 9726 toll free from anywhere in North America or by fax 514 725 5637 or by E mail to info avantron com Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 91 Glossary of Terms ASCH Stands for American Standard Code for Information Interchange The ASCII character set is the most universal character coding set baud rate See speed click To press and release a mouse button quickly command button A button that carries out an action A command button usually has a Label that describes the action it carries out communication port See serial port communications settings Settings that specify how the information is transferred from your computer to a device control menu box The icon that opens the control menu for the window It is always at the left of the title bar database A set of related data tables organized as a group database record Defines a single element of a single element of a relational database file that contains each of the fields defined for the file A record is the logical equivalent of a row of a table double click To rapidly press a release a mouse button twice without moving the mouse download To transfer information from an external data source other computer or equipment to your computer extension The period and up to three characters at the end of a filename An extension usually identifies the kind of information the file contains file A block of info
16. AT 2000R RQ Other TCP IP Parameters In order to provide complete flexibility to introduce your AT 2000R RQ Spectrum analyzer in your network there are a few other parameters the user has access to via TELNET as described below Subnet Mask This mask allows the server to decide at connection time whether a given TCP IP host is part of the local network segment so that packets can be Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 38 routed properly A default subnet mask is created automatically when the IP address is configured but can be overridden EX CHANGE SUBNET MASK 255 255 255 0 Name Resolution Hosts on TCP IP networks generally have a text hostname and a numeric IP address The network interface module of the 2000 series analyzer can resolve text host names into the numeric equivalents needed for most connections provided that a DNS domain name server has been configured EX CHANGE NAMESERVER 192 0 1 167 A default domain name can also be configured for the purpose of name resolution When a user types a host name the network interface module will add the domain name and attempt the connection EX CHANGE DOMAIN badger incorp com Gateway TCP IP networks rely on gateways to transfer network traffic to hosts on other networks The network interface module will learn which hosts are gateways for the local network by listening to broadcasted IP routing packets or it can be explicitly told whic
17. AT 2000R RQ Spectrum Analyzer was inspected and passed all final operational and quality control tests prior to being carefully packed for shipment The AT 2000R RQ should be activated as soon as possible after receipt to verify that 1t operates in accordance with the specifications listed in this above manual The default settings when shipped from the factory are the following Mode Spectrum Analyzer Span Full span 5MHz 1G Hz Resolution Bandwidth 1MHz Sweep Time 30 milliseconds Amplitude 30 dB of input attenuation To check out the operation of the Spectrum Analyzer follow these steps Turn the unit on When the unit has passed it s initial self test and calibration it will display the spectrum analyzer screen with the factory set defaults see above 3 If the unit finds an error in the self test it will display error messages on the screen during the boot up sequence 4 If the main electronics passed the boot up self test but there is an RF error in self calibration then the AT 2000R RQ will display a uncal message below the Avantron logo at the bottom left corner of the screen 5 Press MENU the time date temperature and battery voltage will display across the top of the screen 6 Using the Rotary Knob or Arrow Keys select the FREQUENCY COUNTER function Single Carrier mode and apply a stable CW RF signal of known frequency and level such as 40 MHz E 10 dBmV 7 Press ENTER to activate the
18. AT 402P CATV Measurement Option Carrier measurement Precision frequency counter In service HUM C N CSO and CTB Digital Channel Power Field unit Low Level Non Interfering Forward Sweep only Requires Headend Sweep Reference Generator Model AT 2000G Software option for Return path balancing Requires Model AT BAS 1 Bi directional 2 carrier Return Alignment Headend unit and a portable 2 carrier signal generator such as Model AT 402P Baseband NTSC video output High capacity battery Kit provides 1 hr additional operating time approx 3 5 hr 10BASE T Network connection RJ45 for AT 2000R RQ 3 Year Calibration Program AT 2000R RQ Extended Warranty option additional 1 year for a total of 3 years 1GHz Low Level Non Interfering Forward Sweep Reference Generator Bi directional 2 Carrier Return Alignment Headend Unit Specify 2 Input Frequencies from 5 to 50 MHz and Telemetry Data Out gt 50 MHz Portable 2 Carrier Signal GeneratorS6 dBmV Max Out 20 dB adjustment Freq range 5 108 MHz Windows PC Software for 2000 Series A99026010 A99026020 WinCom Data Management Software Includes Disks and User Manual 1 license per PC WinRemote Remote Control Spectrum Analyzer Software Includes Disks and User Manual 1 license per PC Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 13 Optional Accessories for 2000 Series Pv1 PSC2000 PSC2220E PSC2004 PSC2224E A90093030 A91001
19. Battery Charger is capable of supplying sufficient current to both power the unit and charge the battery the charge time will be lengthened if the unit is operating The DC external power source vehicle battery should be capable of providing a minimum of 2 Amperes at 12 VDC Due to the nature of the power supplies and battery charger in the unit an input voltage below 12 VDC can draw excessive current and damage the internal circuitry The 3A three Ampere fuse in the DC vehicle cord will prevent damage to the Model AT 2000R RQ Any attempts to power the Model AT 2000R RQ from an external power source other than the provided Power Supply Battery Charger or the provided DC power cord may result in poor operation or damage to the Model AT 2000R RQ Receiving amp Unpacking The Model AT 2000R RQ Spectrum Analyzer is carefully packed at the factory using a specially designed shipping container to prevent damage during transit The shipping container must be inspected prior to accepting delivery If any exterior damages are present notify the transport carrier immediately Avantron is not responsible for damage caused during shipping Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 15 Carefully open the shipping container without destroying it Remove the equipment and once again inspect it for damage Test the AT 2000R RQ operation using the procedure listed in the INITIAL CHECKOUT section If damage or defec
20. From the SWEEP menu on the AT 2000R RQ a Sweep Normalise function is initiated See NORMALIZE PROCEDURE in order to fully correct the frequency response signatures of the Sweep Reference Generator and the Sweep Analyzer The Model AT 2000G is connected at the headend as referred to in diagram Avantron recommends installing a directional coupler between the channel combiner network and the outgoing trunk The coupler value should be chosen so that the coupled tap loss of the coupler and the internal attenuator of the AT 2000G allow adjusting for proper operational reference sweep test signal levels Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 83 SWEEP OUTPUT OUTPUT TO HEADEND SYSTEM CHANNEL COMBINER DIRECTIONAL COUPLER 8 12 or 16 dB TESTPOINT TO SET SWEEP PILOT LEVEL AND TEST FOR NON INTERFERENCE Connecting Sweep Generator at Headend The directional coupler should be connected so that the Output port is connected to the channel combiner and the AT 2000G is connected to the coupled port or tap which will allow the test signal to be combined with the system output and directed toward the distribution system Use a length of coaxial cable no longer than necessary to reach from the AT 2000G output to the directional coupler NOTE Avantron recommends connecting a standard TV set on the outgoing trunk test point and checking for any noticeable interference The proper output level of the A
21. Just as the overall quality of the viewed TV picture is affected by video noise prior to modulation and transmission the noise floor of the RF transmission system can adversely affect the transmitted RF channel This is logical as the ideal carrier and consequently the TV picture created would have an infinite range above the noise floor of the system creating a noise free picture As this is not technically possible a balance must be struck between a level that is too high thus creating an excellent Carrier to Noise but a poor Carrier to Composite Triple Beat Subsequently a carrier that is too low in level would create an excellent Composite Triple Beat but a poor Carrier to Noise ratio This is especially true as the nature of RF amplifiers creates a 3 dB degradation in the Carrier to Noise ratio every time the number of amplifiers in cascade is doubled This means that for a 16 amplifier cascade there will be a degradation of 12 dB in the Carrier to noise ratio i e it doubles four times 1 to 2 2 to 4 4 to 8 and finally 8 to 16 amplifiers 4 doubling x 3 dB per doubling a total degradation of 12 dB The only good news is that the cascade must be doubled in length from 16 amplifiers to 32 amplifiers before the next full 3 dB degradation occurs This does emphasise the critical nature of the set up of these line amplifiers C N Test Procedure The AT 2000R RQ can perform C N tests in 3 different ways Method 1 In
22. MEASUREMENT ANALYZER OPTIONAL ON AT 2000R eessen 68 INTRODUCTION TO DIGITAL MEASUREMENTS rettes t testte stette tette etrs rereset errete sreree renn 68 Quadrature Amplitude Modnlatton rana nana nena nen n nn nnn arca nn rana cra nncnnacnnns 69 DOCSIS Gnd SS ANNEX Ba lao a 69 TESTING QAM SIONS eege ege todada E A EES eege eege leas tes 72 Pre and RE 73 Modulation Error Ratio MER 74 Estimated Noise Margin ENM oi ai eiii 73 Error Vector Magnitude EVM ccccccsccccsssscscessnseceeconsecessnnsecessnseecessnsesceensecessaneecensnsescseansesesenucesenenseeeennses 75 CONSTEELATION DISPLAY EEN 76 EE 76 STATISTICS EE REENEN T7 TEE 77 ADAPTIVE EQUALIZERDISPLA Y ti Ee 78 BAS 1 BI DIRECTIONAL ALIGNMENT OPTIONAL ssssssssssssssssssssssssssssssssssssssssssssssssssssessssssssssssesees 79 MODEL BAS 1 HEADEND UNT diia 79 MODEL AT402P 2 CARRIER GENERATOR 80 OPERATING BAS 1 OPTION ON AT 2000R RQ 1 0 eeeeessscececeeeeesseneeeaececeeseessaceeeceeeeseesnaaeeececeeseessaaeeeeeeeeseeseaaeeeee 80 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 3 KE SI NON INTERFERING RF SWEEP SYSTEM OPTIONAL sccscsssssssssssscrseesssesssesssessssssssssessssssseesesssees S2 INSTALEING S WEEP SYSTEMinii dt ea 83 NORMALISING SWEEP RESPONSE 3 OPERATING SYSTEM SWE P Seege eegen AE age eege ee EES ee ia dadas ETO 86 Sweep Display Selec cti A ic 86 AVANTRON SERVICE AND SUPPORT o cocococococonoconoconoconoconocon
23. Where such designations appear in this book they have been printed with initial capital letters AVANTRON the AVANTRON logo are registered trademarks of AVANTRON TECHNOLOGIES INC Microsoft Windows is a registered trademark of Microsoft Corporation Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 5 Introduction Welcome The Avantron Spectrum Analyzer Model AT 2000R RQ is a portable battery operated RF Spectrum Analyzer which will prove itself to be an invaluable multifunction tool for broadband RF testing This is due to its inherent broad input range high sensitivity and advanced circuit design characteristics You may perform daily testing and preventative maintenance as well as locate faults and perform trouble shooting The Model AT 2000R RQ is a designed for the field portable instrument The base function is an advanced digital spectrum analyzer which also may optionally include features required for CATV and other broadband testing One button measuring of signal levels with various correction factors for different modulation types measurement of Carrier to Noise Ratio Composite Second and Composite Triple Beat distortions as well as Hum Modulation and QAM digital measurements An integrated Frequency Counter can measure any CW AM FM or Television signals Avantron has skillfully combined many unique features and functions in a single state of the art microprocessor controlled instrument Thi
24. cable TV measurements Modulation Error Ratio 10 X log average symbol power average error power dB Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 74 Estimated Noise Margin ENM The ENM or ESTIMATED NOISE MARGIN is an indication of the headroom of the system It is calculated from the MER taking into account modulation type 64 256 symbol rate and bandwidth It assumes noise disturbance only other disturbances will give a false ENM The headroom is related to the critical operating level or le 8 uncorrected error rate at which point impairments are visible in a picture Visual Constellation examination is a way of diagnostic for signal disturbances Pure Thermal Noise appears as cloud around the ideal point getting lighter as it expands Other typical transmission disturbances have characteristics visual effect phase noise appears as crescent shaped constellation points more apparent on the outer edge because of angular shift of the signal coherent distortion or CW interference appears as doughnut shaped constellation points all over because of the sum of different frequency vectors Signal and Interference amplifier compression appears as shift toward center for the outer edge points because it more severe on large amplitude it may be associated with phase shift AM to PM conversion Error Vector Magnitude EVM EVM is the measurement of modulation quality of the transmitted sig
25. frequency counter Verify that the frequency and level displayed is precise 9 If the frequency and level is correct the AT 2000R RQ is functioning normally Na oo Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 18 Understanding the AT 2000R RO This section will help you to become familiar with the front panel keys and the general operation of the Model AT 2000R RQ You will find detailed description of the front panel and an explanation on the use of features AutoCalibration The AT 2000R RQ automatically calibrates itself to the current ambient temperature and then monitors that temperature as the testing is completed It is fully calibrated to traceable standards and includes built in computer generated calibration data in non volatile memory AT 2000R RQ s On Line Help Context related help screens can be called up any time during the operation of the instrument This feature offers the user an operators handbook at the touch of a finger When performing tests in a particular mode the HELP system is continuously available to assist the user with step by step instructions Throughout the operation of the AT 2000R RQ the HELP system can offer tips and reminders as well as detailed descriptions of each menu function Spectrum Analyzer Help The Spectrum Analyzer is a full featured test instrument with many features designed to make it easy to use The default softkey menu al
26. noise of the analyzer Step 4 Press ENTER to confirm that all of the steps have been performed and the measurement will proceed The results will be displayed at the bottom of the screen and will show the frequency the measured C N ratio in dB and the Noise near Noise Correction factor used in the calculation It is recommended that measurements be made with as little noise near noise correction as possible C N Gated in service and Channel Edge Method These methods do not require the removal of the RF carrier or modulation of the channel under test but sometimes under some circumstances is a slightly less accurate method and should be used only as a reference One cause for this is that the line selected for the Gated test may not be free of noise A quiet line inserter could be used at the Head End to do just that insert a quiet line Follow instructions supplied with inserter Step 1 Tune to the carrier frequency or TV channel by any of the methods already described in this manual Step 2 The input attenuator should be set to so that the system noise is at least 10 dB above the internal noise of the analyzer The AT 2000R RQ will auto range the attenuator when measuring the carrier level Step 3 With the softkey menu select the following combination Fl gt SINGLE F2 gt C N F3 gt GATED CH EDGE F4 PRE FILTER gt YES Recommended to prevent overloading the analyzer user supplied equipment and insta
27. powerful feature is extremely helpful when aligning the system response and analysing different RF signatures The Recall Superimpose function will work in all the AT 2000R RQ operating modes The superimposed trace will appear in a specific colour on the screen To superimpose a trace fTT 3048 ors ode KEE Sweep 4 PF 50 700 MHz p p anu CF 500 009 MHz SPAN 680 MHz SET TILT press on the RECALL e ES key on the front panel SZ SE and then from the on screen menu select RECALL RECORDS F1 Using either the spin knob or arrow keys Pg Dn Pg bUp you can scroll through the records and select the proper trace to su SET TILT FREQ 50 5568 SPECTRUM ANALYZER NORMALIZE MULTI CARRIER Min On High be displayed With the 4 TILT na 50 558 trace highlighted press the ENTER key to display To clear the superimposed trace simply press the light blue MEM C key on front panel Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 29 Erasing Records And Settings Stored records or settings that are no longer needed or that have been transferred or printed should be erased to free up memory for adding new records To delete only a few records use the spin knob to scroll through v Mode Comment Date Time the on screen records or SA INGRESS TEST AT NODES 18 19 97 68 15 57 DCP DIGI PWR ON QAM SIGNA 16 19 97 08 20 12 SA PEAK HOLD ENERETURN 24 the arro
28. settings ALPHA NUMERIC KEYS Use alpha numeric keys for entering frequency channel span etc If an entry from the numeric keypad does not coincide with an allowed function value the analyzer defaults to the nearest allowable value FUNCTION KEY Located to the right of LCD display provides soft key menu selections Top key is F1 to bottom F6 STORE Press to store test data or the instrument setup Store documented measurements and trace records in non volatile memory for later viewing printing or transfer to PC compatible computer RECALL Press to access RECALL menu and select F1 RECALL RECORDS to retrieve stored records for viewing printing or superimpose on live trace for comparing Press F2 RECALL SETTINGS to activate previously stored instrument setups PRESET Press to clear current instrument settings and return to factory default settings Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 21 HELP PRINT COMM ESC MEM zZ Sl z e BKSP ENTER J Fir gh HELP Access context related help screens which can be viewed during the Operation of the instrument PRINT Press to print the screen s contents directly to a parallel type printer You may choose Epson compatible or HP Laserjet compatible print driver modes in the setup parameters COMMUNICATIONS This function key enables the built in communications software to download and upload files by using a sta
29. starting with A5 91 25MHz are all evenly spaced at 6 0 MHz intervals HRC and IRC are other Channel Plans available with different offsets This creates some unique intermodulation problems in amplifiers The potential for the creation of intermod or just beats for short is there This is obviously due to the simple quantity of RF signals present in the passband and with these carriers having the same spacing is what generates the beats that actually add with each other at 6 MHz intervals CTB is the power addition of the beats created in the system very typically is at its worst in the centre of the occupied band As an example the number of signals at the centre frequency of a 60 channel system is greater than 1 350 This area has the best potential for this type of intermodulation During the test sequences the AT 2000R RQ will apply a correction factor for Beat Near Noise Correction The beat correction factor obtained when the internal noise of the spectrum analyzer is compared to the measured system noise in dB will be displayed separately at the bottom of the screen although the value is already added to the CTB measurement displayed CTB In Channel Method ONLY Step 1 Tune to the carrier frequency or TV channel by one of the methods previously described The input attenuator can be set to view on screen the carrier being measured however the AT 2000R RQ will auto range the attenuator when measuring the carrier leve
30. to perform the test on if not already tuned The AT 2000R RQ will auto range the attenuator while performing the test Press ESC if necessary to return to the top level of function key menus to display the QAM choices To tune while in the QAM mode press the blue FREQ key on the front panel At this point you can key in a specific frequency then from the on screen menu select F1 CENTER FREQ Once you have entered the proper frequency press the ESC key to bring you back to the QAM menu Step 2 Set the QAM parameters for the type signal being Seen tested Select F5 SET Leg Be Mer QAM PARAMETERS Interleave gt 1 lt 3 t Modulation Type Set for 64 or 256 QAM Symbol Rate Can be user set from 1 000 to 7 000 MS sec Default values are 64QAM 5 057 and 256 QAM 5 360 lt Kaob arrous gt Liao lt Esc gt Qeit witheut sawe lt Enter gt Eeit Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 12 Polarity Type Default setting is Automatic User selectable for Normal or Reverse Reverse is used with IF signals from modulators before up conversion Compensation On Off Default setting is ON For 256 QAM setting only Interleave gt I lt 1 to 255 Most transmission equipment has a default setting is 128 Interleave gt J lt 1 to 255 Most transmission equipment has a default setting is 001 Once all settings have be properly entered select the F5 INIT QAM
31. 00R RQ spectrum analyzer Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 33 Avantron WinCom for Windows To use Avantron WinCom you must retrieve a Records Database file which can then be transferred to a WinCom Database a PC based database file Retrieving measurement data from Avantron instruments requires that you establish a communication connection with an Avantron Model AT 2000R RQ spectrum analyzer A Records Database file is where you store your measurement data information on an Avantron instrument and is limited to 100 records or traces A WinCom Database is a Windows PC based file that supports unlimited number of records or traces The information that you record about your measurement traces includes date time instrument serial number user name company name temperature instrument calibration date etc Avantron WinCom ME E File Edit View Communication Options Help M WinCom Database file content File Transfer 4 Records Database File content fecords2 Records bin User ld ROGER ld Mode Comment aj Upload i M lode Coment 1 ae y Erster 2 SA TEST TRACE 2 TEST TRACE 2 RARR OSA RARTEST RARTEST OFFICE SLM6 MULTI CH OFFICE MULTI CH OFFICE OFFICE SA CH 116 CH 116 NewTr SA Fort Worth Dallas Fort Worth Dallas NewTr SA Jones Jones Properties i Properties Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 prelimina
32. 2 way broadband network The output test point of most line amplifiers will serve as a typical return path input Figure 3 AT402P 2 carrier generator Operating BAS 1 Option on AT 2000R RQ When the Model BAS 1 receives these carriers the LOW and HIGH status LED s will illuminate to indicate that the presence of in bound test signals was detected The BAS 1 measures the actual amplitude levels in dBmV and converts the results to numerical data which is transmitted using an FSK modulated telemetry carrier The transmission of the data on a carrier frequency within the forward path bandwidth standard 52 MHz will complete the loop from field to headend as well as headend to field The BAS is a special function tunes a single emu C BAS BIDIRECTIONAL ALIGNMENT SYSTEM J FSK FREQ 52 000 MHz SET FSK _ FREQUENCY programmable a frequency and looks for the modulated data carrier transmitted at 52 MHz or other customs frequencies from the BAS 1 headend unit While in this position screen will show a dual za bar level display SIGNAL MEASURE SPECTRUM EE ANALYZER If a BAS 1 FSK data e carrier is not present the LO FREQ HI FREQ LEVELS Hi dBmU Hi dBmU az dB display will show NO SIGNAL or if carrier is present but no data is modulated upon it the upper display will shoe NO DATA If a BAS 1 data carrier with modulated data is present the display wi
33. 252 A91001270 A65000909 A99025600 AT2CASE Quite Line Inserter for in service distortion testing 2 Amp Battery Charger AC Power Supply for AT 2000R 110 60 2 Amp Battery Charger AC Power Supply for AT 2000R 220 50 4 Amp Battery Charger AC Power Supply for AT 2000RQ 110 60 4 Amp Battery Charger AC Power Supply for AT 2000R Q 220 50 Model BTA Bucket Truck Adapter AT 2000R Replacement battery 12V 5 A h AT 2000R RQ Replacement High Capacity battery 12V 7 A h Requires AT2HCBAT Serial Cable for PC connection DB9 to DB9 Padded Protective Soft Case for AT 2000R RQ Hard transport protective case for AT 2000R RQ Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 14 Accessories A C Charger Power Supply Depending on the application one of two battery chargers may be supplied For 120 VAC applications the power supply battery charger is rated at 120 VAC 50 60 Hz primary and 12 VDC at 2 0 Amperes For 220 240 VAC applications the power supply battery charger is rated at 240 VAC 50 Hz primary and 12 VDC at 2 0 Amperes Using a power supplies chargers with a lesser or greater rating may damage the power supply battery charger and the Model AT 2000R RQ Please contact Avantron if you need to power the AT 2000R RQ from other than an already approved source CAUTION The external power jack can receive power either from the provided Power Supply Battery Charger or the DC vehicle cord The Power Supply
34. 256 is represented by 4 4 8 bits In practice QAM modulation uses the same size set in both I and Q such as 16 64 and 256 plus 32 and 128 In the latter two cases the full constellation is not used in the far corners The allocation of the symbol bits to each of the location of the constellation is the Mapping Finally each constellation point in the rectangular plane can be defined by I and Q values but it can also defined in a polar plane as a Vector with an amplitude and an angle QAM is two amplitude in quadrature or one complex modulation with amplitude and phase DOCSIS and J 83 ANNEX B DOCSIS or Data Over Cable Service Interface Specification is a standard developed to provide a common set of rules enabling interoperability between transmitting equipment and receiving equipment through a transmission channel In order to achieve this interoperability with various makes and designs the standard defines in details normal operation and recovery mechanism This detailed specification minimizes different interpretations by various designers that leads to non interoperability DOCSIS covers at length the data transmission protocol and interface to the cable network For the downstream transmission modulation it refers to another standard defined by the ITU International Telecommunication Union in its Digital Television J series of Recommendations J83 covers cable delivery and its Annex B covers a specific case of QAM 64 and QAM256 Th
35. AT 2000R RQ FUNCTIONS u cccssssscsscssecesscscccssssccessscssesssscecessssssesssscseesssscsssssscsessssccsssssseseessoees 26 DEFAULT INSTRUMENT SETTINGS ee Seel eeh EES EE eeh EENS ge EEN ee EE Ee Set 26 el EE 26 STORNO TO MEMORY T ca EE ani ca0Gd dario gn oaanddaaeeuacgiacandd daaGsuanse4esadudaassac sideaets daa sbansehgaaduaaascencauseataaat 26 SLOVE RECOTAS deco dere pi aero doo a cl 26 ANT DA A O 27 E Records is 28 Recall Stored Settings oia iii de Ei aii 28 Superimpose On A Elve Trace iii tiara EE EEN AANEREN EECHER 29 Erasing Records And Settings csccccscccsscsevsssesssessonesevsccevsceoseneseoneveosaeensccensnessoeeseaeesensesenansesonessonesenaceenans 30 ARAN TNG cas 30 Printing Reports And Screens na data EE Eaa danna gedet 30 Print creen MA it 31 Print Multiple Records oia 31 DATA COMMUNICATION A ENEE 32 COMM RS 232 Serial Interface scccescccescccesscceeseeessseceseecescecessecesseeesseesssecesseecesaesesseeesaeessaeessaeeceaecesaeeesaes 32 Upgrading nee da 32 AT2000R RO User EE LE E EE E LEE 33 Avantron WinCom for Windows 34 Avantron WinRemote for Windows ooonoccnnnccnnancnnnnnnonanonnnnonnnnonnn canon nn rana conan anar cnn ne nnn nena nnrnn arco cnc annncrnacinns 35 ETHERNET IOBASE T INTERFACE RJ 45 OpTONAL 36 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 2 Confisuring IP Address ia li 36 Other FEP P EE EES Ee EES 38 SETUP USER bBRrERENCES trocet erstetosse
36. Advanced Test Equipment Rentals www atecorp com 800 404 ATEC 2832 EEN Established 1981 Avantron 2000 Series Portable Spectrum Analyzer Avantron AT 2000R RQ User Manual Version 4 0 preliminary _Abionon Avantron Technologies Inc The OTHER Spectrum Analyzer Company the MSOs Trust CONTENT INTRODUCTION EE 6 WELCOME AAA EEEE A A E E A 6 AT lt 2000R RO SPECIFICATION So ee Sdet ee GEO ed enea O Tr rie eeh Ree See EN eege 8 CATV Measurement Kpeciecoatton e nec nnnnnnennnnnn nr nnnnn nec nana nnn naar non rnnnnnnecnonnnncnnnnnnos 10 Digital Measurement QAM 64 256 Kpecifiecotteone nc nono nan nn rana conan cnn nc rana crnna ninas 12 Available Options for 2000 Serie 13 Windows PC Software for 2000 Series 13 Optional Accessories for 2000 Series 14 ACCESSORIES ds 15 A C Charger Bower Suppl i 15 RECEIVING amp UNPACKING ide 15 WARRANTY INFORMATION ENEE 17 GETTING STARTED asertas onstan eass sosse degt Sege ei egeged Aeddi EEs oar disnea 18 INN AAA A EE 18 UNDERSTANDING THE AT 2000R RQ seeesseeesssoesssoessssoessssocsssocesesocesssoessssoesssoosossocsssssessssoessssosssssssesssessssose 19 AUTOCAEIBRATION EE 19 AT 2000R RO S ON LINE e EE 19 FRONT PANEL KEYS sia 20 Marks et 20 KEE 20 Key Description Push Buttons 21 MATN MENU SOFTWARE EUNCITONS pi e EE EES auase 23 Standard Functions ANd Jon 24 Optional Functions Gnd CONS ee EEN EEEEEE SOEN NEESS 24 Optional CATVPAK Functions and konse 25 BASIC
37. Channel Requires the removal of either the carrier or its modulating signal at the system head end The unit will prompt you through the measurement steps Once the test is terminated save the results for future reference Method 2 Gated This totally non intrusive method measures the channel noise of a selected line during the vertical blanking period of the video signal Method 3 Channel Edge Uses the channel edge where the noise floor in the guardband is scanned to find the lowest level The automated tests for carrier to noise are pre programmed by Avantron to calculate the C N for an NTSC TV modulated channel and compensate for an effective video bandwidth of 4 MHz It is Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 59 recommended that the noise to be measured be greater than 10 dB over the internal noise of the AT 2000R RQ Spectrum Analyzer The use of a pre selector bandpass filter maybe required if the RF energy content is high due to the number of carriers During the test sequences the AT 2000R RQ will apply a correction factor for Noise Near Noise Correction The noise correction factor is obtained when the internal noise of the spectrum analyzer is compared to the measured system noise in dB This reading will be displayed separately at the bottom of the screen and the value is already included in the C N measurement C N In Channel Method Step 1 Tune to the carrier frequency or TV chann
38. T 2000G is established at the point where no interference is observed on the TV monitor Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 84 Normalising Sweep Response The NORMALIZE function will correct the frequency response signatures of both the AT 2000G Reference Sweep Generator and the AT 2000R RQ Sweep Analyzer The initial setup the AT 2000R RQ and the AT 2000G Test Identifier fPilot MHz TxSerialNo Comment Generator to be 2 0459 0997 NODE 7A connected directly to each other using the same cable which will be used in the final hook up so that the sweep response signatures can be normalised l Set AT 2000G attenuator for proper system operation Typical level of the pilot carrier is between 16 to 20dB below the visual carrier levels Using a television monitor set the pilot level with the front attenuator just below the threshold of interference 2 Enter SWEEP mode on the AT 2000R RQ and select F4 to begin the normalise procedure 3 A table will pop up to indicate in which of the 10 slots the curve will be stored Hi lighting one of the choices and pressing F6 key will select the slot and start the normalise function WARNING Do not disconnect RF input of the AT 2000R RQ until the procedure has completed otherwise the sequence will have to be repeated Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 85 Operating System Sweep
39. The AT 2000R RQ SWEEP mode operates in conjunction with the AT 2000G Test Generator When this mode is accessed the AT 2000R RQ must lock on and synchronise to the 50 7 MHz reference pilot carrier that is generated by the AT 2000G If the reference pilot is not present when this mode is selected the AT 2000R RQ will return to the Spectrum Analyzer mode In SWEEP mode the SPAN is continuously variable from Max Span of 1000 MHz to as little as 10 MHz Vertical scale can be toggled between 10 5 2 dB div A system tilt value as well as start F1 and stop F2 frequencies can be entered to compensate the displayed trace This will bring trace back to a flat display so that proper peak to valley measurements can be made using H1 and H2 The tilt value effects the portion of the displayed sweep between the Fl and F2 frequency points Markers if desired can be set by pressing the MARK key and accessing the MARKER MENU See the Marker section for more information on how to set markers NOTE To normalise the AT 2000R RQ Sweep Analyzer with an AT 2000G Test Generator select F4 NORMALIZE Connect AT 2000R RQ directly to AT 2000G generator output and follow instructions on the screen Sweep Display Selections Several Digital Averaging ATT 3008 ors oqp System Sweep 7 PF 50 790 MHz AVERAGE options are available from emu CF 588 988 MHz SPAN 1909 MHz gt 3MIN the DISPLAY softkey max FILTER gt 0FF ON Seck rn
40. alyzer User Manual 4 0 preliminary 51 Precision Frequency Counter To access the Frequency Counter just return to the MAIN MENU and select the FREQ COUNTER icon The Model AT 2000R RQ features a extremely precise frequency counter measurement function The FREQUENCY COUNTER allows you to measure both carrier frequencies and levels very accurately The built in frequency counter is as accurate on CW carriers as it is on modulated AM FM or TV channels The counter displays frequency with a 10 Hz resolution while the accuracy is delivered through the stable 1 PPM reference time base As an example for a frequency of 100MHz the accuracy would be 100 X 1 which is equivalent to 100Hz Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 52 CATVPAK Automated CATV Measurements Optional The Avantron Model AT 2000R RQ is a versatile instrument that can be configured with various options to allow you to create your own unique test system This combination of field portable spectrum analyzer and modular options provides expanded measurement capabilities for future technologies or individual specialised requirements Digital Channel Power Maintaining the correct arr 2508 ors oap CPigital Ch Power py 4 00 MHz carrier power levels ss SS 326 290 MHz ahh 2 MHz BANDWIDTH throughout your system is crucial in both analog and digital cable g 4 systems Unlike the measurement of analog visua
41. anty is in lieu of all other warranties expressed or implied and no representative or person is authorised to represent or assume for AVANTRON any liability in connection with the sale of our products other than set forth herein Repairs and or calibration is typically completed in 5 to 10 working days Shipping costs are paid by the factory only when returning equipment to a customer following warranty repair It is the responsibility the customer to notify the factory technical support persons prior to shipping products for servicing since many times problems may be solved over the telephone saving the user more precious time and shipping costs AVANTRON maintains regular office hours from 8 00 AM to 5 00 PM eastern time Monday through Friday A toll free 800 number and e mail address for technical and sales support are provided below North America Toll Free 800 297 9726 E mail address for Sales or Technical Support info avantron com Typical warranty on our products covers all parts and labour as well as software and required hardware updates The warranty period starts from the day the equipment is delivered however AVANTRON extends a grace period of 60 days after the end of the official warranty period to cover any contingencies Please note that the warranty period for rechargeable batteries is three months Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 17 Getting Started Initial Checkout The Model
42. appear in the FREQ menu Select Video Carrier F2 or Audio Carrier F3 puts the AT 2000R RQ in TV channel tuning mode Simply entering a channel reference as per CHANNEL PLAN SETUP will automatically tune to the frequency that coincides with the channel allocation The spin knob and arrow keys can be used to scroll up or down the in the channel tuning mode incrementing the frequency as per the channel allocations in the CHANNEL PLAN Span The SPAN control key accesses the soft key menu which includes span related functions such as F1 MAX SPAN and F2 ZERO SPAN These keys speed up the process of going from any span to maximum 1000 MHz span or to minimum 0 MHz span When the SPAN is selected the default function allows you to enter a value in MHz and press ENTER J key The spin knob and the arrow key also increment the span settings Spans are variable from a Max Span of 1000 MHz to as little as 100 kHz and then Zero Span Zero Span The Zero Span menu da CF 500 000 MHz E des eg E gives you access to the is a a a a ES SCH built in AM FM i2 LOG gt AM FM demodulator You can detect aural signals by 6 tuning a specific ae tip frequency and activating C dy the audio demodulator a Vu with F2 LOG AM ai FM 90 Toggle between log ase S scale AM detector with roo VOLUME Jo AP of modulation scale and FM detector with deviation scale in kHz RESOLUTION BANDWIDTH VOLUME
43. are update files on disk or they can downloaded from our web site at www avantron com A password is required to access the download section that is obtained by contacting Avantron customer support The firmware file has the extension udf When Upgrade Firmware is selected from the communications menu a dialog box will appear and you select location of the firmware file and double click on it to start the upgrade procedure Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 32 AT 2000R RQ User Files The following files are formats available on Avantron AT 2000R RQ spectrum analyzer products All instrument files have the bin file extension and can be downloaded or uploaded to and from the instruments Below is a short description of each file and its purpose Records bin This is the database where all measurement records and traces are stored Settings bin The settings database contains stored instrument setups Using the same settings files are multiple units helps speed up measurements in the field and provides some consistency on the measurements even though they are done by different technicians each using their own AT 2000R RQ spectrum analyzer Plans bin Contains channel plans for NTSC PAL or other world standards Colors bin This file that contains the customized color settings used on the Avantron AT 2000R RQ spectrum analyzer Param bin This file contains user preferences on Avantron AT 20
44. ave your model and serial number ready e After receiving the authorisation number RMA return the equipment with an accurate description of the symptoms and be sure to state the authorisation number on your paperwork Transportation charges to Avantron is the responsibility of the client e Original packaging is preferred If unavailable carefully package the equipment in alternate packing material to ensure adequate protection during shipping Avantron s Responsibility e Avantron will acknowledge the receipt or the returned equipment and at that time bring any discrepancies to your attention e Avantron will replace or repair at it s discretion any component or sub assembly it deems necessary to return the unit to a proper condition e After the necessary repairs Avantron will undergo complete test and re calibration e Every precaution is taken by Avantron to ensure that every unit meets all electrical and mechanical specifications prior to returning the equipment to the client Note Avantron is not responsible for failures caused by transportation to from the customer s location nor by rough handling by the customer after receipt Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 90 causing further damage to the product Avantron is solely responsible for the defects stated above and in our standard product warranty policy If you require information or assistance contact Avantron at 800 297
45. cent and dBc decibels below carrier level C N CSO CTB This unique TEST option is a feature that integrates 3 measurements into one C N CTB and CSO are performed separately or simultaneously combined to reduce the number of signal interruptions on a CATV system This feature is very practical and useful for FCC type proof of performance testing In Channel Freq In Channel Frequency Response are measured quickly accurately and in service using multiburst test signal in VITS lines of a video channel Depth of Mod The video depth of modulation screen provides percent modulation in both graphical and precise numeric format Test signals transmitted on the VITS of program video provides a standard to calibrate the video depth of modulation Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 25 Basic AT 2000R RO Functions Default Instrument Settings Preset The light grey with red lettering PRESET key resets the AT 2000R RQ to a known default state The Model AT 2000R RQ is factory set to default to the Spectrum Analyzer mode with full span 1000 MHz Resolution Bandwidth of 1 MHz Sweep Time of 30 ms and 30 dB of input attenuation Storing To Memory Microprocessor power adds expanded storage capabilities Measurements traces and instrument settings are stored as records in non volatile memory for later viewing printing or transferring to PC compatible computer Ease of use and time saving bei
46. ds by awaiting the 2 incoming CW carriers e g 6 amp 29 MHz The technician injects the CW carriers on the return signal path at the field amplifier test point using a AT402P Dual Carrier Signal Generator field unit e g 6 amp 29 MHz The BAS 1 at the headend monitors the return signal path and will then measure the actual levels of the incoming test signals The BAS 1 then transmits the measurement results 1BmV readings in real time mode on the forward path using an FSK modulated data carrier at 52 MHz or whatever custom frequency you may desire The field technician using the AT 2000R RQ equipped with the optional FSK data carrier decoder will read the data on the forward path at 52 MHz and will simultaneously display both CW carrier level readings as measured at the headend by the BAS 1 headend unit Model BAS 1 Headend Unit The Model BAS 1 is connected at the headend where typical return in bound signals are to be monitored The BAS 1 output telemetry carrier m st be connected do the Figure 2 Model BAS 1 Headend Unit forward path headend combiner where the data transmitted at 52 MHz other freqs Available can be fed out on the forward path of the broadband coaxial system Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 79 Model AT402P 2 Carrier Generator In the field the Avantron AT402P serves to inject a LOW and HIGH eg 6 and 29 MHz CW test carriers on the return path of the
47. e data stream in Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 69 this process is referred to as MPEG2 which is another standard this one covers a transport stream of digital television that has been compressed according to algorithms of the Motion Pictures Expert Group The picture encoding is followed by channel coding before transmission while at the reception the reverse processes are applied in reverse order The picture encoding according to MPEG2 process is a compression of the digitized picture to reduce the required bit rate for transmission It uses the human vision physiological response to reduce redundancy both in time and space in motion picture Reference picture frames are transmitted regularly but in between these motion detection and differences are transmitted The MPEG also defines transport stream packets of compressed that can be multiplexed multiple pictures sounds or ancillary data The basic packet has 188 bytes including one Sync byte and 24 bits of Packet Identification Data In some instances 16 bytes of error correction codes are added 204 bytes packets but are unused in the Annex B Although data e g cable modem or telephony can replace compressed video it still uses the MPEG Transport Stream format The J83 Annex B channel coding goes through the following process The sync byte of the 188 packet is replaced by a parity checksum such that at the reception after calculation o
48. e solutions vary by country If you have questions about the services described below please refer to the section Technical Support at the end of this chapter At Avantron we get everyone involved and trained to handle Customer service and support requirements This assures our customer that there is always someone that can be reached at a moment s notice Avantron also provides sufficient product training to regional Avantron representatives allowing them to actually provide some of the product support locally and in a prompt and personalised manner AT 2000R RQ Maintenance RF Connector Replacement Since the RF input and output connectors may receive many insertions per day of coaxial cable the life of the connectors can be fairly short The connectors are a 1 GHz rated common type F double female that can be easily replaced with the aid of a 7 16 inch wrench No case disassembly is required Exact replacement F connectors are available from AVANTRON Battery Pack Replacement Sealed Lead Acid batteries will last for hundreds of charge discharge cycles 1f properly cared for However after the normal lifetime of service the battery pack will need to be replaced This requires some disassembly of the unit To replace the battery pack perform the following steps 1 Remove the unit from its optional canvas carry bag 2 Remove the six 6 Phillips screws on the upper rear of the AT 2000R RQ unit 3 Slide the upper cover toward
49. e symbols are mapped to the I and Q modulators Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 70 J83 ANNEX B SYMBOLS 6 bits 3 in 1 3 in Q 8 bits 4in1 4 in Q SYMBOL RATE 5 056941 Ms s 5 360537 Ms s 2697035 Mb 3581070 Mb Raw bit rate and channel 30 341646 Mb s 88 88 42 884296 Mb s 90 5 throughput Baseband filtering Square root raised cosine 18 Square root raised cosine amp 12 FEC framing 42 bit trailer for 60 FEC blocks 40 bit trailer for 88 FEC blocks each block 128 symbols of 7 bits each block 128 symbols of 7 bits Interleave Level 1 Level 2 I 128 J 1 I 128 64 32 16 8 Level 2 J 1 2 3 4 5 6 7 8 16 lt 128 64 32 16 8 1 2 3 4 5 6 7 8 16 Channel coding Reed Solomon 122 128 Trellis coding binary convolutional 4 5 punctured INTERLEAVE PROTECTION I OF TAPS J INCREMENT BURST PROTECTION LATENCY QAM 64 QAM 256 QAM 64 QAM 256 128 default setting 1 default setting 95us 66us 4 0ms 2 8ms 0 22 0 15 pa wine EE 379 264 CC EE 664 462 28 19 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 71 Testing QAM Signals To access the QAM mode select the QAM ANALYZER icon on the Main Menu or from Digital Channel Mode select F2 QAM ANALYZER The default conditions for QAM mode is Constellation Display set for 64 QAM operation Step 1 Tune to the center frequency of the digital signal that you want
50. ed clearly and graphically on the AT 2000R QAM Analyzer s full color high resolution active matrix LCD screen Display modes include e Constellation Display with zoom capabilities e Error Statistics Graph Display e Adaptive Equalizer Display Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 68 Quadrature Amplitude Modulation Quadrature Amplitude Modulation is a modulation scheme that generates a set of modulation values that comprises the superposition of two separate modulations on two carriers that share the same frequency but are 90 apart or in quadrature For instance QAM 16 has a set of 16 values 4 in each of the I or IN PHASE and Q or QUADRATURE Each of the two carriers is modulated with a set of 4 values 3 1 1 3 as the two modulation data are independent we can generate a set of 16 4 x 4 The generation of QAM with quadrature carriers and modulators is a very convenient physical circuit It can also be used at reception to separate the complex incoming signal into 2 simpler signals It is also very useful to visualize the symbol set of values in a plane where Abscissa X is the In phase and Ordinate Y is the Quadrature We then have a constellation where each value of the set is clearly positioned Back to our QAM 16 I and Q set of 4 values are represented by 2 bits for a total of 4 bits by symbol Similarly QAM 64 has a set of 8 x 8 64 values represented by 3 3 6 bits per symbols QAM
51. el by any of the methods already described in this manual The input attenuator can be set to view on screen the carrier being tested however the AT 2000R RQ will auto range the attenuator when measuring the carrier level Press ESC if necessary to return to the top level of the function key menu which displays the C N choices Step 2 With the softkey menu select the following combination F1 gt SINGLE F2 gt C N F3 gt IN CH F4 PRE FILTER gt YES Recommended to prevent overloading the analyzer user supplied equipment and installed at the input of AT 2000R RQ also allows for the reduction of attenuation for the measurement of noise NO lf no filter used Step 3 Press the IN SE gt SINGLE dBmU VIDEO 2 CF 55 258 MHz 22 7 dBmU SPAN 18 MHz MEASURE F6 key to 2s start the measurement The AT 2000R RQ will measure the peak amplitude of the test carrier and the internal a aie E E noise of the Analyzer WITT JI semi and temporarily saves as ico e E them The AT 2000R RQ will then prompt the user to SE SS Wa dB er MHz 3 8 a AVERAGE 2 REMOVE THE TEST Am ra COMBINED gt C N CTB cso gt IN CH GATED CH EDGE A A ee Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 60 CARRIER AT HEAD END or at this time remove the modulation and reduce the attenuation to obtain a noise measurement at least 10 dB above the internal
52. eliminary 6 may be observed instantly and precisely The Model AT 2000R RQ also enables you to listen to signals at the center frequency in zero span with the built in AM FM demodulator This is an invaluable aid in identifying interfering signals and ingress The Model AT 2000R RQ ensures you of speed and accuracy when taking measurements At power up the analyzer automatically performs a self check on internal components and is ready in seconds It constantly monitors internal temperature as well as battery level with warnings for out of calibration conditions This automatic and continual monitoring with stored calibration curves ensure always consistent and precise digital measurements within the specified limits Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 7 AT 2000R RQ Specifications Note All specifications apply over the standard 0 C to 50 C operating temperature range after a minimum of 2 hours of storage within the operating temperature range if the unit is not fully at ambient temperature The AT 2000R RQ meets all it s specifications within 1 minute after it is turned on providing that the AT 2000R RQ is within the one year calibration cycle Avantron s unique AutoCal feature assures accuracy by periodically self testing itself and triggering a non obstructive calibration as required FREQUENCY Frequency range 1 MHz 1 GHz Frequenc
53. ements being performed by various users Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 27 Recall Stored Records To recall any stored record for viewing and printing access the RECALL RECORDS directory by pressing the RECALL key on the front panel and from Comment CH_A ANALYZER DISPLAY FREQUENCY COUNT CH 2 CH 2 TU CHAN MEASURE SYSTEM AGC LEVELS HEADEND LEVELS AND FR CN CH 2 IN SERUICE DISTORT TEST CH 2 BAS OPTION TU CHANNEL CH 2 COMBINED TEST P DIGITAL PWR VIDEOWAY the on screen menu FM SIGNAL 10 KHZ FIL PEAK HOLD INTERFERENC select RECALL e PU OUT OF SPEC H SINGLE CH RESPONSE use the spin knob or SUCKOUT PROB 200M ON SUCKOUT arrow keys Pg Dn d AM DEMOD Pg UpT to scroll through the stored records in the directory as well as any that may have been compressed To view a record on the screen select DISPLAY ITEM F1 Records that were stored using the AUTOTEST ATCATVPAK option required function on the Main Menu can be recalled on screen and scanned channel by channel To view the results of each signal carrier select EXPLORER F5 from the on screen menu and use either the spin knob or arrow keys to scroll through the information Recall Stored Settings Recalling settings is just as easy as storing them You may select them by Comment ES SA INGRESS TEST AT NODES pressing the RECALL PEAK HOLD IN RETURN key and then by Ee Seege ge E SWP HIGH RES REF AT H
54. ency 1 PPM Resolution 10 Hz Visual Aural Delta Frequency Range 1 10 MHz ACCULACY nn 200 Hz Resolution 10 Hz Visual Aural Delta Amplitude 0 75 dB for S N gt 30 dB Digital Carrier Measurement Amplitude Range 30 to 60 dBmV Resolution 0 1 dB Absolute Accuracy 1 5 dB Bandwidth Range 200 kHz to 200 MHz FM Deviation Range 150 kHz CCUTACY 2 kHz 1 75 kHz 5 kHz to 150 kHz HUM Low Freq Disturbances Modes CW or Video In Service Range 1 10 CCUTACY 0 5 from 1 to 5 1 from 5 to 10 Modulation Depth AM Range
55. enu SWITCH POSITION F4 and continue programming the rest of the display bars to your needs Press the ESC key and the AT 2000R RQ will read the levels of the six carriers AUTOTEST The Model AT arr 25a8 os oo EEN mens 2000R RQ uses one of m A A A Abe two modes to perform To E 2 SZ an AUTOTEST One p mode is levels only and 5 ll the other is levels and frequencies All tagged LEVELS amp FREQ SPECTRUM ANALYZER channels and Laag 7 STOP frequencies in the active A Channel Plan will be CARRIER tested An entire IW SWEEP headend can be ES e i tel d and VIDEO 7 175 26323 MHz 22 5 dBmU A Y SCAN an Amon AUDIO 7 179 76324 MHz 7 9 d n measured within a a 4 50001 MHz 14 6 d n minute An additional mode CARRIER SWEEP allows a continuous scan of channel levels Although the display can be used to evaluate frequency response this is not an accurate representation and should be used as a reference only To get an accurate frequency response of the system a true sweep test should be performed by using the low level non intrusive Sweep option for the AT 2000R RQ Both system sweeping and measurement tests can be performed simultaneously Select the channels and set the frequency offsets if required in the CHAN NEL PLAN which can be accessed from the SETUP menu See section 4 4 1 Edit Plan for de
56. er a second of errors that cannot be corrected and are feed to the end user The BER Pre FEC is obviously always higher than BER Post FEC typically Pre FEC will increase with noise input while Post FEC remains 0 until very close to loosing lock where it increases very rapidly Other disturbances than pure noise such as burst interference have different effect Burst interference may affect BER Post FEC even for a low BER Pre FEC if its duration exceeds the burst protection period as seen in the interleave section BER is displayed in scientific notation The more negative the exponent the better the BER The AT 2000RQ has a range of 1 0 x 10 to 1 0 x 10 Better than 1 0E 8 is required after FEC for system to operate properly By looking at the Pre FEC and Post FEC BER you can determine how hard the FEC is working to correct errors The harder it s working the closer the system is to failure Modulation Error Ratio MER MER is the best overall figure of merit measurement to determine 64 256 QAM signal RER 24 8 dB quality MER provides an indication of transmission impairments MER indicates the ratio of average total signal power in the ideal constellation to average error power in the constellation as received by the AT 2000RQ QAM analyzer The measurement includes error power due to any impairment MER is expressed in dB where higher is better MER is analogous to a composite ratio of signal to noise and distortions in analog
57. ers makes it entirely invisible to the signals carried by the network including scrambled TV channels data FM carriers and specialized pilot carriers Real time update of thousands of data points per second means exceptional resolution while eliminating rubber screwdriver effects Yet in the field the operator has full control to zoom in to any portion of the band for precise alignment Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 82 Installing Sweep System The system functions with the optional Model AT 2000G RF SWEEP TRANSMITTER In order to avoid any interference on the network it is essential to inject the reference sweep test signal at correct levels before making the hook up shown in Figure 26 Two signals are transmitted by the AT 2000G a fixed frequency reference pilot at 50 7 MHz custom frequencies available and a 5 to 1 GHz sweeping test signal Biz Ee e Model AT 2000G Sweep Generator The reference sweeping test signal of the AT 2000G is maintained at a level of approximately 20 dB below the pilot carrier level thus the AT 2000G output pilot signal is normally set at a level of approximately 20 dB below the lowest video carrier level when combined with the system channels On initial set up the Avantron model AT 2000G RF SWEEP TRANSMITTER and the AT 2000R RQ must normalised by connecting both units directly using the same cable length which will be used in the final hook up
58. ess log amplifier etc There are several ways of entering the DISTORTION MEASURE mode From the MAIN MENU by pressing the MENU key on the front panel and select the HUM MOD or C N CSO CTB icon If already in spectrum analyzer mode press the ESC key and then select DISTORTION MEASURE F4 Now from this screen select C N CSO CTB F2 this will bring you into the desired screen now go ahead and perform your tests Hum Modulation Measurement To enter the HUM E mode you can go to the as CF 500 000 MHz mee MAIN MENU and gt select HUM or if you r are already in the qq PAS Spectrum Analyzer mode simply press the ESC key and from the on screen menu select DISTORTION MEASURE F4 and then select HUM F1 CR A SE E SIG TYPE gt cw VIDEO HUM SIGNAL 4 1 39 dBc y wa HUM MARKER 4 6 39 dBc Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 56 Hum modulation is generally caused by line power related AM modulation As defined for Cable Television it is the total peak to peak power line hum and low frequency AM modulation at all frequencies from DC to 1 KHz expressed as a percentage relative to the peak level of the reference carrier Hum that is power line related causes rolling bars to appear on the television screen Generally these bars will start to appear at a distortion level of about 2 If one is visible this indicates a 60Hz hum and if 2 bars
59. h hosts are gateways EX CHANGE GATEWAY 192 0 0 66 Once all of your parameters have been entered follow the steps below 1 Enter the Command lo Logout The following screen should appear Corren Edt Lee 7 Lastreeix MSS100 Version 943 5 6 981019 Type SELF at tee Local_2 gt prompt for assistance sername user Lecat _ D set priv Correci n da hedt kut Password Loca1_2 gt gt chage ipe ress 192 iere TCP esers exist rebos iecel_2 gt gt le Exitieg the Laatroniz M53100 2 Reboot the AT 2000R RQ by switching it off for at least 30 seconds 3 Don t forget to set the same IP address settings of the PC computer being used to communicate with the AT 2000R RQ Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 39 Setup User Preferences The Model AT 2000R RQ initial settings can be customised according to individual user requirements The two main items that are user defined are system Fl PARAMETERS and screen display F2 COLORS If the optional CATV MEASUREMENT PAK is installed a third item will appear in the SETUP mode F3 CHANNEL PLANS Access to SETUP is done from the MAIN MENU If not already in the MAIN MENU simply press the MENU key on the front panel and select SETUP The SETUP screen will then appear fig 9 Set up Screen The SETUP screen C Setup 7 displays important Paraneters Setup information about your MODEL AT2000R
60. idth settings affect the sensitivity by changing the signal to noise ratio Attenuator settings affect the level of signal passing through the input of the instrument whereas the resolution bandwidth affects the level of internal noise without affecting the signal Visibility of a signal that is still near the noise can be improved by using digital averaging functions found in the TRACE control menu Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 50 Markers Two vertical markers and two horizontal markers can be used to set level and frequency references The vertical Vl and V2 markers indicate the frequency and in certain appropriate spans the level is also displayed When both markers V1 and V2 are selected and displayed on the screen while in the 5 1 1 MHz span div the delta level is automatically calculated The horizontal H1 and H2 markers indicate reference levels only When both reference markers are displayed on screen the delta levels are automatically calculated This is especially useful for peak to valley measurements Marker values will remain current until new data is entered Press ESC to end Marker functions and go back to the previous menu FS V1 gt CF and F6 V2 gt CF Tunes Analyzer center frequency instantly to V1 or V2 marker frequency Especially useful for rapidly tuning between two reference carrier frequencies Avantron AT 2000R RQ Spectrum An
61. ime is automatically set to a value that is inversely proportional to the square of the resolution bandwidth In order to use the fastest sweep times use the widest Resolution bandwidth that still allows you to distinguish between the various signals to be measured The Model AT 2000R RQ has 8 different Sweep Time settings to choose from 3 mS 6mS 15mS 30 mS 100 mS 300 mS 1000 mS and 3000 mS Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 49 Video Bandwidth VBW FS VBW The Model AT 2000R RQ has 3 different video bandwidth settings to choose from 1 MHz 100 kHz and 10 kHz Amplitude F1 Attenenuator Variable 65 dB attenuator Select input attenuation by increasing or decreasing in steps of 5 dB F2 Reference Level Sets top of the screen reference level in steps of 1dB F3 Vertical Scale Select vertical scale by toggling between 10 dB to 5 dB to 2 dB div F4 Reference Offset Set reference level offset value from 40 to 40 dB All level readings will automatically be compensated This function is useful when working with amplifiers or other equipment that have test points All that has to be done for TestPoint TP compensation is to enter the value of that TP Sensitivity Measuring Low Level Signals Spectrum analyzer sensitivity is the ability to measure low level signals and is limited by the noise inside the spectrum analyzer The spectrum analyzer input attenuator and resolution bandw
62. ing BAS 1 Option on AT2000R 82 Operating System Sweep 88 Operating Time 9 pilot 85 PLAN MANAGER 46 POWER key 22 Power Off Beep On Off 43 Power Off Timer 42 73 74 Precision Frequency Counter 53 Preprogrammed settings 28 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 94 PRESET key 22 PREV MODE key 22 PRINT key 23 printer driver 43 printer drivers 31 Printer Type Epson Hp 43 Printing reports 56 proof of performance testing 31 RBW 50 RECALL key 22 RECALL RECORDS directory 29 Recall Stored Records 29 Recall Stored Settings 29 Reference Level 51 Reference Offset 51 report headers 32 Resolution Bandwidth 50 Return in bound signals 81 Returning Equipment 92 RF Input Connector 90 RS 232 Serial Interface 33 RS 232C 23 Screen Colors 44 Sensitivity 51 Service Centers 91 Setting FSK Receive Frequency 83 Setup Screen 41 SITE ID 27 Soft Keys 21 SPAN menu key 22 48 span related functions 49 Storage capabilities 27 STORE key 22 Store Records 27 Store Settings 28 Stored records 31 Superimpose on live trace 22 Superimpose On Live Trace 30 Sweep Display Selections 88 Sweep Normalize 85 Sweep Test Generator 88 Sweep Time 50 SWT 50 Tag records 31 Test signal 85 Time 43 TRACE memu key 22 TRACE menu key 48 Transferring to PC 27 TV Channel Mode 55 Typical return path input 82 User Identification 43 User Pa
63. ion Printer Type Epson Hp Toggle between an Epson compatible printer driver and a HP LaserJet print driver Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 42 Custom Screen Colours The Model AT C Color Setup Custom User 2 4 DEI 2000R RQ has an ahan Graphic Bkg WHITE INDOOR 15 7 Tt CONDITIONS excellent colour TFT Graphic Bkg WHITE i i i active matrix LCD 5 Graphic Line BLACK ae Grid BLACK HA screen display Unlike _ menory BLACK Ee Markers BLACK CRT displays this type Sen De of LCD panel has esse Text sack Editor Bkg WHITE distinct advantages It Cos raitor text BLacK remains in perfect focus CUSTOM USER 1 CUSTOH USER 2 while displaying lt Arrows gt Switch Color H lt Knob gt Switch Item CUSTOM exceptional detail on a Lol ne save USER 3 640 x 480 pixel display es lt Esc gt Cancel fo 4 kar i The recessed polarised WW ve custom po ER USER 4 screen 1s bright and clear and is viewable even in direct sunlight The added value of colour makes using your Model AT 2000R RQ much easier to use since individual components of the screen colours can be customised The COLOR SETUP screen shows the 9 components of the screen in which the colour can be edited Graphic Background Graphic Line Grid Memory Markers Edge Background Edge Text Editor Background and Editor Text The soft key menu on the righ
64. is 192 0 1 200 When using a 2000 series analyzer in a Network without a gateway it is necessary to configure it s IP Address to have the same base address as the Network Here are the steps to follow to modify the IP Address of the AT 2000R RQ spectrum analyzer 1 Connect the analyzer to one of your hubs or directly to your PC s network card with an inverted RJ45 cable 2 Configure your computer on the same hub or with the direct inverted cable to have the same base address as the analyzer but to have a different IP Address For example you can use the Address 192 0 1 10 3 From the start menu select RUN 4 Type telnet in the dialog box as shown below Run HE Type the name of a program folder document or Internet x resource and Windows will open it for you A Telnet None tx Connect Edit Terminal Help Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 36 6 Select Connect gt Remote System from the menu The following dialog box should appear 7 Type in the default IP address of the AT 2000R RQ spectrum analyzer 192 0 1 200 and click Connect The following screen will appear Telnet 192 0 1 200 Connexion Edition Terminal 2 E Lantronix MSS166 Version U3 5 6 981619 Type HELP at the Local_2 gt prompt for assistance Username gt IT s Type in any username the name is not important in the next screen you will see we typed the name user
65. iver for bi directional system alignment Functions with Avantron Model AT BAS 1 Headend Bi directional Alignment System Digital Ch Power The average power of digitally modulated carriers such as 64 and 256 QAM can be easily and accurately measured This function supports the latest digital technologies and is simple to use allowing you to set center frequency and channel bandwidth QAM Analyzer The built in digital demodulator makes it possible to measure in service 64 256 QAM digital signals Displays Constellation with zoom capabilities Adaptive Equalizer Display Pre and Post Bit Error Rate BER Modulation Error Ratio MER Error Vector Magnitude EVM Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 24 Optional CATVPAK Functions and Icons TV Channel Allows the selected TV Channel to be measured with better than 200Hz resolution The Amplitude in dB is also displayed Multi Carrier The display allows quick RF amplifier setup by scanning up to 6 user selected reference carriers The markers function in this mode and can be used to measure deltas in level This is a convenient feature to determine RF amplifier tilt slope and gain settings Auto Test Allows the selected tagged Channels listed in the active channel lineup to be measured with better than 200Hz resolution The Amplitude in dBmV is also displayed Hum Allows the Hum Modulation Distortion to be measured Result is in peak to peak per
66. l Press ESC if necessary to return to the top level of function key menu which displays the choices Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 62 Step 2 With the softkey menu select the following combination F1 gt SINGLE F2 gt CTB F3 gt IN CH F4 PRE FILTER gt YES Recommended to prevent overloading the analyzer user supplied equipment and installed at the input of AT 2000R RQ allows for the reduction of attenuation for the measurement of the Analyzer noise floor NO If no filter used Step 3 Press the MEASURE F6 softkey to start the measurement During the test the AT 2000R RQ measures the peak amplitude of the test carrier and the internal noise of the Analyzer and temporarily saves them The AT 2000R RQ will then prompt the user to shut off the test carrier or the modulation and reduce the attenuation to obtain a beat measurement at least 10 dB above the internal noise of the analyzer Step 4 Press ENTER I to confirm that all of the steps have been performed and the measurement will proceed The test results will be displayed at the bottom of the screen and will show the frequency where the measurement was taken the measured CTB ratio in dB and the Beat near Noise Correction factor used in the calculation It is recommended that measurements are made with as little noise near noise correction as possible Composite Second Order CSO Composite Second Order Prod
67. l carrier level si St ERR ppp average channel power in a digital system is a wide bandwidth measurement The AT 2000R RQ spectrum analyzer carries out the measurement by sweeping the channel and taking an average of the power levels at each measurement point across the trace SPECTRUM T l i i i i l fe Aenea por ANALYZER i i i l AVERAGE 2 1 MEASURE Set the centre frequency and the bandwidth of the channel to be measured default bandwidth is 6 MHz Pressing the F6 MEASURE initiates an automatic sampling of the power at many points within the selected bandwidth and sums them all integrates Averaging and corrections are applied to the measurement and displayed in both dBmV and equivalent dBm Typical amplitude of digital carriers on a mixed broadband system analog digital channels should about 10 dBc relative to analog visual carrier peaks Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 53 Frequencies and Levels TV Channel Mode Select TV CHANNEL from the Main Menu screen The TV CHANNEL ATT 30 dB OFS 9dB Ac mode provides the asnu ounen 2 cr 55 250mM2 DERIER gi FREQUENCY capability to make accurate level and E eee oai frequency CARRIER measurements The MM one built in fr equency E i _ e CARRIER counter Measures D N modulated video and audio carriers as well as 28 4 5 MHz intercarrier spacing with a 10 Hz
68. ll show the carrier levels measured by the BAS 1 at the headend Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 80 The left display bar indicates the low frequency carrier amplitude and the right display bar indicates the high frequency carrier amplitude A delta differential in dB is also displayed which is convenient for determining tilt Setting FSK Receive Frequency The BAS FSK receive frequency is displayed at the top of the BAS mode screen 1 To set the BAS FSK receive frequency press the F1 softkey 2 If the value is incorrect use the backspace key to erase the figure 3 Enter the new frequency with the numeric keys the alpha function is automatically disabled 4 Once the new value has been entered press the ENTER key to save the new value Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 81 Non Interfering RF Sweep System Optional Low Level RF Sweep testing remains the one of the best tools for adjusting RF frequency response and analyzing a whole frequency band The Avantron Model AT 2000R RQ optional low level synchronous RF Sweep System does not disturb the reception of distributed signals This is accomplished by a reliable tracking spectrum analyzer approach to frequency response testing which doesn t require an elaborate setup The RF sweep signal is simply integrated with the other signals using a standard RF coupler A level of 35 to 40 dB below the carri
69. lled at the input of AT 2000R RQ allows for the reduction of attenuation for the measurement of the Analyzer noise floor NO If no filter used Step 4 Press the MEASURE F6 key to start the measurement During the test the AT 2000R RQ will measure the peak amplitude of the test carrier the internal noise of the Analyzer and measures the system noise during the vertical blanking pulses of the video signal Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 61 The results will be displayed at the bottom of the screen and will show the frequency the measured C N ratio in dB and the Noise near Noise Correction factor used in the calculation It is recommended that measurements be made with as little noise near noise correction as possible Composite Triple Beat CTB The CTB interference is formed by the mixing of carriers Composite third order distortion is the ratio expressed in dB of the peak level of the RF signal to the peak of the average level of the cluster of distortion components centred around the carrier frequency Composite Triple Beat is created as another type of third order intermodulation It is unique to CATV as the majority of the CATV channels in the Standard Channel line up set up have exact spacing of 6MHz from each other i e channel 2 visual is 55 25 MHz channel 3 visual is 61 25 MHz With the exception of channel 5 which is spaced 1OMHz from channel 4 The remainder of the CATV channels
70. lows selection to different tuning methods F1 CENTER FREQUENCY F2 VIDEO CARRIER CATU PAK OPTION F3 AUDIO CARRIER CATY PAK OPTION A second top level submenu for direct access to the other available main analyzer functions is activated by pressing the ESC key F1 SYSTEM SWEEP Allows direct access to RF Sweep function V1 4 lt Knob gt Line lt Arrows gt Page lt Esc gt Quit lt Enter gt Top 0f File To access help select the HELP function key The spin knob scrolls the text line by line while the arrow keys scroll page by page The ENTER 4 key allows you to return to the start of the text Press ESC to end HELP and return to the previous mode of operation Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 19 Front Panel Keys Menu Keys The blue keys labelled FREQ SPAN AMPL are all examples of front panel keys which access menus of functions that are displayed along the right side of the display These menus are called soft key menus NTE anana f d s ta la Ka Figure 1 Model AT 2000R RQ Soft Keys The soft keys are the six push buttons arranged vertically and located on the right side of the colour LCD screen The function for each key corresponds to the description displayed on the on screen menu along the right The soft key menu which will vary depending on the test mode of the analyzer and will allow for certain changes such as fo
71. n the received packet a valid sync byte is regenerated The next step is Reed Solomon Forward Error Correction codes insertion the block size is 122 data symbols 6 FEC symbols at 7 bits per symbols there is no relationship between MPEG transport stream packets and FEC blocks Interleave is applied to the FEC blocks that means that blocks are not transmitted as generated but stored and then transmitted starting by the1st bits of a series of blocks and then the 2nd bits and the 3rd in practice 128 blocks of 128 bits are interleaved in the QAM 64 level 1 while level 2 allows reduced and enhanced interleave for both QAM64 and QAM256 land J parameters commonly default I 128 and J 1 the purpose of interleave is to disperse adjacent bits in a FEC block such that a burst error will affect a few bits in a large number of blocks rather than many bits in a small number of blocks The interleaved data is then framed with a synchronization sequence in QAM 64 there is a trailer of 42 bits for 60 FEC blocks and in QAM 256 it is a 40 bit trailer for 88 FEC blocks The data is then randomized to prevent long strings of 1 or 0 Trellis coded modulation is then applied to the modulator symbols 6 bits for QAM64 and 8 bits for QAM256 the purpose of trellis coding is to enhanced the distance in the constellation plane for adjacent transmitted symbols hence reducing the effect of noise and distortion at the reception Finally th
72. nal before the forward error Eug 2 9 e correction stage EVM will indicate how much interference or distortion is present on the signal If there is significant degradation on the signal the constellation points will become unclear and the decoder may not be able to reconstruct the received signal correctly The AT 2000RQ QAM analyzer demodulates the QAM signal equalizes and then calculates the average size of the error vector in relation to the maximum symbol magnitude Error Vector Magnitude maximum symbol magnitude rms error magnitude X 100 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 75 Constellation Display When measuring the quality of digital signals it is very useful to see the graphical representation of the constellation The Constellation Display shows both the I in phase component and Q quadrature component values Each location on the constellation is framed by decision boundaries If the signal falls within these boundaries the correct data will be received The data is in error if it falls outside of its boundaries into adjacent location such as when the signal is affected by noise or other interference Significant degradations in the signal scan be identified including noise coherent interference and transmission distortions as well as modulator impairments such as I Q imbalance or quadrature error Understanding the constellation display can help in quickly troubleshoo
73. ncy then from the on screen menu select CENTER FREQUENCY F1 Once you have entered the proper channel or frequency press the ESC key to bring you back to the HUM screen Step 2 Now the selection of doing the test on a CW or Video Carrier must be made If the test is to be made on a CW make sure that there is no modulation present otherwise the readings will not be accurate Select your choice from the on screen menu SIG TYPE CW VIDEO F4 by toggling the key gt indicates choice Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 57 Step 3 The AT 2000R RQ will automatically set the instrument settings and sequence the test The real time hum is displayed in dBc decibels below reference carrier and in percentage Combined C N CTB and CTB This mode combines all the measurement requirements for C N CSO and CTB With the exception of CTB all measurements can be done in service with ATT 25 dB OFS dBmU VIDEO 2 C N CSO CTB 7 CF 55 258 MHz 22 7 dBmU SPAN 18 MHz 25 gt SINGLE COMBINED gt C N CTB cso gt IN CH GATED CH EDGE the powerful GATED Measurement feature gt PRE FILTER This mode also allows for an individual measurement or as a Combined Test for saving time and memory space when storing C N 47 5 dB 3 8800 MHz 3 0 dB AVERAGE 2 MEASURE WARNING Verify that the analyzer is not being overloaded A quick indica
74. nd COMMENT fields as well as time date external temperature user ID and last calibration date The stored records can be accessed by using the RECALL key on the front panel and selecting from the on screen menu RECALL RECORDS F1 Store Settings Complete Model AT 2000R RQ instrument settings may be stored Storing settings is very simple Set up the instrument to make the desired test with the desired frequency or channel position along with span attenuator settings bandwidth adjustment etc necessary to make the specific measurement and store those settings by pressing the STORE key and then from the on screen menu select the STORE SETTINGS F2 function Give this setting a unique ID 8 char max by using the alphanumeric keypad or optional keyboard if unit has been installed with this option After entering your ID press the ENTER key at this point a comment box will appear where you can enter some additional information max 40 char Each stored setting will contain full front panel settings and information entered in the ID and COMMENT fields as well as the time and date The stored set tings can be accessed by using the RECALL key on the front panel and selecting from the on screen menu RECALL SETTINGS F2 Selecting a stored setting instantly prepares the Avantron for a specific measurement This feature simplifies repetitive measurements and can assist in creating company wide standards for individual measur
75. nd serial number last factory calibration date of the instrument as well as the all basic information such as DATE TIME TEMPERATURE COMPANY NAME and USER NAME Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 31 Data Communication COMM RS 232 Serial Interface The Model AT 2000R RQ has a standard RS232 communications serial port interface A 9 pin D type connector is located in the front panel connector compartment behind the drop down door Activating the COMM function will set the Model AT 2000R RQ as a file server allowing you to access the contents of the non volatile memory as if it were a disk drive on a PC Avantron s software must be installed on a PC and executed before communications can be made with the AT 2000R RQ through a standard null modem cable When the transfer has been completed press the ESC key to exit the server mode and return the AT 2000R RQ to the normal mode of operation The maximum rate for serial communications is 57 600 baud This manual covers the Model AT 2000R RQ functions and operation only Consult the documentation accompanying the Avantron software for more information on using serial communications features Upgrading Firmware WinCom features a function that simplifies the process of upgrading your Avantron 2000 series instruments By pressing the Comm function button on the keypad will put the AT 2000R RQ in communication mode Avantron provides firmw
76. ndard RS 232C connection ESCAPE Press to back out of menu or soft key function selections MEMORY Allows operator to temporarily store a screen trace in a temporary memory You may use to compare a live trace to the one in temporary memory This trace may also may be saved STORE volatile memory if desired by using the key MEMORY CLEAR Used to clear the trace in temporary memory or one that was recalled and removes it from the screen display BACKSPACE Press within a keyboard command to delete or correct preceding characters ENTER This key is used to confirm and save all entries or commands CURSOR Up Arrow key moves items upwards or towards the right hand side CURSOR Down Arrow key moves items downwards or towards the left hand side KNOB The rotary spin knob allows continuous change of values of many functions that change in increments only such as center frequency reference level and marker position Clockwise rotation of knob increases values Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 22 Main Menu Software Functions The MENU key accesses the Model AT 2000R RQ Main Menu screen In the center of the screen are icons with text description for each available function mode and selected for direct access to various test options and setup functions The rotary spin knob or the arrow keys may be used to scroll through the icons and use the ENTER key to select the function At
77. ne packet has an uncorrected error Post FEC sg SES or SEVERELY ERRORRED SECOND within each measurement second the ratio of errored packets to transmitted packets is higher than a user settable threshold between le 4 to le 2 FLS or FRAME LOSS SECONDS within each measurement second there has been at least one Frame Lock Loss UNAV or UNAVAILABILITY TIME there has been at least 10 consecutive SES Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary TT During statistics gathering period MER EVM ENM a graph is dynamically updated as well as ES SES FLS and SUT time markers At the end of the set period all measurements are recorded and can be visualized globally or one can zoom into details The recorded measurements for BER Pre and Post are that of the total period but during the measurement period the dynamic values second per second are displayed Adaptive Equalizer Display Digital signals are very susceptible to reflections in the cable These can be caused by a number of different problems such as bad splitters loose or bad connectors as well as damaged cables These reflections can cause errors in the data transmission To resolve potential problems due to reflections the digital receivers such as set top converters have an adaptive equalizer that senses the amount of reflections and compensates for them The receiver manufacturer will recommend a maximum correction specification This dis
78. ng a primary objective the Model AT 2000R RQ allows you to store measurement records as well as instrument settings Up to 100 measurement records and 64 instrument settings can be stored and later selected from the RECALL RECORDS or RECALL SETTINGS directory listing when needed By storing and recalling measurement and or instrument test settings time savings can be realised by the test and maintenance personnel This time savings directly translates to cost savings and therefore the equipment will tend to pay for itself more quickly with improved staff efficiency Store Records The STORE interface is simplified by reducing the number of keystrokes required to store a measurement A SITE ID and COMMENT field has been provided so that the user can enter specific information which will be saved along with the measurement results records To store the record simply press the STORE key on front panel and then from the on screen menu select the STORE RECORDS F1 function Give this record a unique ID 8 char max Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 26 by using the alphanumeric keypad or optional keyboard if unit has been installed with this option After entering your ID press the ENTER key at this point a comment box will appear where you can enter some additional information max 40 char Each stored record will contain full front panel settings and information that was entered in the ID a
79. nlike with analog pictures digital video can appear to operate normally and yet it may be very close to failing Digital measurements will be the only way to ensure that the system is operating well within limits Until now cable operators had to choose between very expensive lab digital test equipment or hand held QAM instruments which means technicians have to carry a second instrument just to test the digital channels These instruments are often limited in performance allowing only forward path measurements Integrating the QAM digital measurements with an affordable field spectrum analyzer such as the AT 2000RQ is truly a breakthrough from both a cost and performance point of view The AT 2000RQ QAM Analyzer features a high performance field spectrum analyzer with a 1 MHz to 1 GHz frequency range high sensitivity and 3 ms scan speed that is the fastest of any CATV spectrum analyzer The Avantron Model AT 2000RQ QAM Analyzer demodulates and accurately measures the QAM signals carried through the cable system It provides the measurement power the field technicians need for the latest 64 256 QAM digital technologies and is very simple to use making the transition from analog to digital testing a breeze The built in digital demodulator makes it possible to measure e Bit Error Rate BER Pre and Post Error Correction e Modulation Error Ratio MER and Error Vector Modulation EVM e Estimated Noise Margin ENM Information is display
80. nsitivity wide dynamic range and simple straight forward controls allows for ease of operation and repeatability This analyzer enables you to view your entire RF spectrum at a glance or select a single frequency for close scrutiny A spectrum analyzer allows for troubleshooting of extraneous signal interference with easy to understand graphical spectral displays It can be used for many applications to locate the source of an interference problem or to optimise RF based equipment alignment Testing and maintenance are easier because the effects of most adjustments can be observed instantly and precisely across the whole 1 GHz spectrum The Model AT 2000R RQ also enables you to demodulate and listen to signals at the centre frequency in zero span mode The AM FM demodulator is a valuable aid in identifying interfering signals ATT 30 dB UBW A 1008 kHz SWT A 30 ms RBW A 1666 kHz OFS 64dB CF 566 666 MHz SPAN 1000 MHz MAX SPAN pal H eer i H PP ZERU SPAN RESOLUTION BANDWIDTH SWEEP TIME A VIDEO BANDWIDTH NO AVERAGE yo SPAN Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 46 Main Control Keys amp Menus There are 5 major control keys which access soft key control menus FREQ F1 CENTER FREQUENCY F2 VIDEO CARRIER available with optional CATV Measurement Pak F3 AUDIO CARRIER available with optional CATV Measurement Pak SPAN F1
81. ntact the nearest Avantron Representative or the factory at 514 725 6652 or by Fax at 514 725 5637 North America Toll Free 800 297 9726 E mail address for Technical Support info avantron com WEB SITE www avantron com AUTHORIZED AVANTRON SERVICE CENTERS Canada USA Avantron Technologies Inc Avantron Technologies Inc 8596 Pie IX Blvd 710 East Ogden Suite 160 Montreal Quebec Naperville Ilinois HIZ 4G2 60563 Tel 514 725 6652 Fax 514 725 5637 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 89 Returning EquipmentTo Avantron Avantron manufactures equipment to very high standards Products are warranted against defects in materials and workmanship as specified in our published product warranty When properly used and operated your equipment will provide many years of service Should it become necessary to return the equipment to Avantron for in or out of warranty repairs or calibration the following steps should be followed Note If products are repaired or altered by persons not authorised by Avantron or not in accordance with instructions furnished by Avantron or if the products have become defective due to a result of misuse improper repair abnormal operating conditions the labour and materials required to effect the changes will be billed at our standard repair rates Customer s Responsibility e Contact Avantron and request a Returned Material Authorisation number Be sure to h
82. ntification 43 Comparing 30 Composite Second Order CSO 64 CONNECTOR REPLACEMENT 90 Context related help screens 20 CURSOR keys 23 Custom Screen Colors 44 Date 43 Date Format 43 Default Instrument Settings 27 41 default settings 19 Deviation kHz scale 49 Digital Averaging 88 Documenting 31 Edit Plan 45 ENTER key 23 Erasing Records And Settings 31 ESC key 23 External power jack 15 FCC Testing and Compliance 32 F connectors 90 FILTER display 88 FM detector 49 Free up memory 31 FREQ menu key 22 48 Frequency Counter 53 Frequency references 22 frequency tuning 48 Front Panel Keys 21 FSK modulated data carrier 81 FUNCTION keys 22 Gated Measurements 60 HELP key 23 horizontal markers 52 Hum Modulation Test Procedure 58 Hum Modulation Measurement 57 Initial Checkout 19 in service 65 Installing Sweep System 85 Interference 86 Invalid Key Beep On Off 43 Key Description 22 KNOB 23 LCD Backlight Off Timer 42 Levels amp Frequencies 56 Log off 25 Log on 25 Log scale 49 Low Level RF Sweep testing 84 Main Control Keys amp Menus 48 MARK menu key 22 48 Markers 22 52 88 Max Span 49 MEM C key 23 MEM key 23 MENU key 22 Menu Keys 21 Model BAS 1 Headend Unit 81 Modulation scale 49 Multi Carrier Mode 55 Noise near Noise Correction 62 63 Non Interfering Rf Sweep System 84 Non volatile memory 22 Normalize 88 Operat
83. oconeconaconaconoconaconoconoconaconoconoconaconoconaconoconoconansass DO AT 2000R RO MAINTENANCE i cos sinc 0025 veeeetcks vb ee ASSA Ear ENEE EECH A aO E RA 88 RF Connector Replacement dadas 88 Battery Pack Replacement Neie e E e RETURNING EQUIPMENT TO ANANTRON a a a e O a A A E O R 90 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 4 Avantron AT 2000R RQ User Manual Information in this document is subject to change without notice and does not represent a commitment on the part of Avantron Technologies Inc The software and or hardware described in this document are furnished under a license agreement or nondisclosure agreement The software may be used or copied only in accordance with the terms of the agreement It is against the law to copy the software on any medium except as specifically allowed in the license or nondisclosure agreement The purchaser may make one copy of the software for backup purposes No part of this manual and or hardware may be reproduced or transmitted in any form or by any means electronic or mechanical including photocopying recording or information storage and retrieval system for any purpose other than the purchaser s personal use without the express written permission of Avantron Technologies Inc Throughout this book trademarked names are used in an editorial manner only and to the benefit of the trademark owner with no intention of infringement of the trademark
84. or when measuring the carrier level Step 3 With the softkey menu select the following combination F1 gt SINGLE F2 gt CSO F3 gt GATED F4 PRE FILTER gt YES Recommended to prevent overloading the analyzer user supplied equipment and installed at the input of AT 2000R RQ allows for the reduction of attenuation for the measurement of the Analyzer noise floor NO If no filter used Step 4 Press the MEASURE F6 softkey to start the measurement During the test the AT 2000R RQ measures the peak amplitude of the test carrier and the internal noise of the Analyzer and measures the system noise during the vertical blanking pulses of the video signal Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 65 In Channel Frequency Response In channel frequency response is a window of amplitude between the vestigial sideband and the aural carrier Uniform response over the channel bandwidth assures proper relative signal levels throughout the system and balanced response at the subscriber s terminal To avoid interrupting program video the in channel frequency response can be made with a vertical interval test signal or VITS The test signal transmitted on the VITS of program video provides the multi burst standard to video frequency response The channel selected should be one that has a VITS signal Press F4 LINE SELECT and select a VITS video line with the multiburst present To se
85. ort measured in bits per seconds BPS The Avantron System Analyzer is set for 115 Kbs test point Name of a file saved in a STAR 2010 device Often called file name text file A file containing only letters digits and symbols A text usually consists of characters coded from the ASCII character set Also known as data file toolbar A group of command button icons arranged horizontally across the top of a window that performs functions that would ordinarily require one or more menu choices upload to transfer your computer to an external device window A rectangular area on your screen in which you view an application Sometimes windows are displayed within other windows Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 93 Index AM detector 49 AM FM demodulator 47 AMPL menu key 22 48 Amplitude 51 AT1000G RF SWEEP TRANSMITTER 85 AT2000R Maintenance 90 AT2000R Spectrum Analyzer Specifications 8 15 17 AT402P Dual Carrier Signal Generator 81 Attenenuator 51 AutoCalibration 20 AUTOTEST 29 45 56 Averaging 88 BACKSPACE key 23 BAS 1 Bi Directional Alignment 69 81 Battery Pack Replacement 90 Battery type 9 Beat Near Noise Correction 64 C N Test Procedure 60 CARRIER SWEEP 56 Carrier To Noise C N 60 CATV distortions 57 CATV MEASUREMENT PAK 45 CHANNEL PLAN 56 Channel Plan Setup 45 COLOR SETUP 44 COMM key 23 33 COMMENT field 27 Company Ide
86. play shows linear ar 2008 6 GAN CUAN Amalyser J SES TERI Sta Ss impairments such as poor CF Sen nen kiz koal Sgraol 3 031 mie EE frequency response BEF freee dch DFE gt EQUAL j SR weg reflection Tap values uen rost Fec ee lt SET QAH PARAMETERS show how hard the equalizer is working to compensate for impairments The display includes a bar graph The AT 2000RQ shows the coefficients of the equalization filter updated every second This is a tool used to diagnose bandpass distortion gain tilt reflections The graph presents the 32 coefficients 8 Feed Forward Equalizers and 24 Decision Feedback Equalizers The 8th coefficient is the main signal path so it is normally very close to O dB gain of 1 The higher the other coefficients the higher the filter needs to compensate distortion hence less headroom As the instrument is not ideal there is always some compensation 3 4 coefficients in the 20 40 dB around the main response and at the 8th DFE a response close to 20 dB this is the SAW filter triple transit response WORE 172 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 78 BAS 1 Bi Directional Alignment Optional The system consists of the BAS 1 Headend unit and the Avantron AT 2000R RQ with optional FSK receiver built in and a AT402P Dual Carrier Signal Generator At the headend the 19 rack mount BAS 1 dual channel receiver stan
87. r different levels of testing or options within the selected mode Depending on the selected mode of operation some of the soft keys will also permit direct access to other test modes without the necessity of returning to the main menu as a time saving feature Although the soft key function keys are not labelled these keys are also known as Fl top key to F6 bottom key Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 20 MENU El SPAN gt lt ke E E lt z o S olle am A 8 oz ss o nm S E ZS fa Gel am SE ea FUNCTION Lo O RECALL Key Description Push Buttons POWER Use to turn the unit s power on or off MENU Access Main Menu screen Provides direct access to various test options and setup functions FREQUENCY Accesses frequency tuning either by entering frequency direct MHz using the video or audio channel number SPAN Access variable span resolution bandwidth RBW and sweep time SW settings AMPLITUDE Access amplitude related functions Attenuator Reference Level Vertical Scale and Reference Offset MARKERS Access horizontal and vertical markers for indicating level and frequency references Also activates dB Hz function TRACE Access signal processing functions digital average 1 digital average 2 Peak Hold or No Average PREVIOUS MODE Allows to return to the previous measurement mode and instrument
88. rameters 41 VBW 51 vertical markers 52 Vertical scale 88 Vertical Scale 51 Video Bandwidth 51 Zero Span 49 ZOOMING 89 Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 95
89. rmation saved in a computer file format The way information is structured in a file icon Graphical representation of an element Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 92 menu A list of available commands in an application window Menu names appear in the menu bar near the top of the window You open a menu by selecting the menu name Modem An abbreviation for modulator demodulator the device that converts digital data to analog signals before sending across phone lines and converts analog signals back to digital data when receiving them parallel port A connection on a computer usually LPTI where you plug in the cable for a parallel printer port A connection or socket on the computer Ports are used for connecting devices such as printers monitors and modems to your computer and for sending information from your computer to the devices Serial ports COM and parallel ports LPT are the most commonly used ports selection To mark an item so that a subsequent action can be carried out on that item You usually select an item by clicking it with the mouse or pressing a key After selecting an item you choose the action that you want to affect the item serial port A connection on a computer usually COM1 where you plug in the cable for a serial device Modems and Avantron System Analyzers are serial devices speed Refers to the rate at which the data is sent through the serial p
90. ry 34 Avantron WinRemote for Windows The Avantron WinRemote software was designed to help you take full advantage of the measurement capabilities of the Avantron 2000 series spectrum analyzer products The Avantron WinRemote gives you remote control spectrum analyzer access to the AT 2000R RQ spectrum analyzer units With the Avantron WinRemote you can fully control the spectrum analyzer functions such as center frequency span resolution bandwidth settings etc Operation has been kept similar to the operation of the Avantron AT 2000R RQ spectrum analyzer whenever it was possible If you know how to operate your Avantron AT 2000R RQ spectrum analyzer you know how to use the Avantron WinRemote Avantron WinRemote will allow you to store and view record traces and also export the measurement data to the Windows clipboard in BMP format Avantron WinRemote capabilities make it easy to display and analyze information on your PC After collecting the data the Avantron WinRemote enables you to analyze and print the measurement traces ATT e OFS G VEWIAS 1006 kHz Zi Mas in nin AAA AAA EIA APPEARS PAE AAA REA TAR d DD DI IIS o DEET bob ss sche e Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 35 Ethernet 10BASE T Interface RJ 45 Optional Configuring IP Address When delivered with the Ethernet option every 2000 series analyzer has a pre configured default IP Address This IP Address
91. s combination of laboratory grade test functions in a designed for the field package allows the user to virtually go anywhere and rapidly align any broadband RF network while instantaneously be able to monitor system performance with documentation capability all in a single portable and lightweight instrument The analyzer has simple and straightforward controls that allow for quick measurements with repeatable tests The analyzer can function with Smart Modes which automate tests and procedures Fully automated Test amp Measurement functions allows the operator to complete tests on multiple frequencies or channels within minutes and store all the results in non volatile memory as an individual record Records may be directly printed out from the Model AT 2000R RQ to a standard parallel printer or may be downloaded to a PC with Avantron s file transfer and data manager software A spectrum analyzer enables you to view the performance of your entire RF system at a glance or single carrier or channel for close scrutiny Troubleshooting for extraneous signals and or interference is easy with the graphical color spectral displays and you may perform these tests virtually anywhere because the Model AT 2000R RQ is lightweight and runs on an internal sealed rechargeable lead acid battery System testing and maintenance are easier than ever because the effects of system adjustments Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 pr
92. s method is convenient if only a few traces are to be printed at any one time To print the screen all that has to be done is to press the PRINT key An error message will appear if there are any problems either with the printer configuration or cable connection If a message fig 8 does appear please verify if proper printer was selected Print Multiple Records To use this method you will first have to access the records Access to the records is by pressing the RECALL key on the front panel From the on screen menu choose RECALL RECORDS Fl Using the spin knob to scroll through the records that are on the screen or by using the arrow keys Pg Dn y Pg Up to access other pages Tag the ones you want to print by pressing the Tag Item F3 key or by pressing the Tag All Items F4 key all the stored records will be printed when the Print Tagged Items F5 key is pressed If a message fig 8 does appear please verify if proper printer was selected Documentation is a critical step for proof of performance or FCC Testing and Compliance CATV Systems are required to maintain a copy of the proof of performance results in a FCC public inspection file for five years In addition to the data from all required tests and test procedures used proof of performance documentation must include all pertinent information about the test equipment being used for the measurements The Avantron report headers have been designed to include the model a
93. s the rear and lift up and out 4 Carefully unplug the two wire terminal connectors and do not short the positive and negative battery connections Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 88 5 Remove the strap that holds down the Sealed Lead acid battery by removing the securing screws one is located on the rear panel and the other is located on the chassis 6 Insert the new battery pack into the battery holder portion of the chassis 7 Re install the hold down strap and chassis screws and reconnect the 2 wire terminal connectors to the replacement battery 8 To reinstall the chassis into the case slide the chassis assembly into the case and replace the six 6 Phillips screws on the upper rear of the AT 2000R RQ unit When re assembly is completed turn the unit on and press the MENU key to show the charge level of the battery If the battery is nearly discharged 10 5 to 11 VOLTS connect the Battery Charger power supply into the mains power and the AT 2000R RQ turn the analyzer off and allow the battery to charge at least 6 hours Technical support Avantron is located on the Eastern Time zone with regular office hours from 8 00AM to 5 00PM A toll free number service covering all of North America is provided at no charge Key Avantron personnel can always be reached any time of the day through a toll free number or electronic mail service over the Internet International Customers should co
94. scroll through the picture this indicates a 120Hz hum Some television receivers are more sensitive than others and will show up the distortion at a lower level When the hum level starts to reach the 3 5 and higher the picture may start to tear along the edges It is a good practice to document the hum levels at your test points and watch for any major changes during routine maintenance Observing a significant change indicate that there is a potential problem in the offing The cause could be a power supply connection passive or an amplifier As an example here are some possible causes of hum Low line voltage causing the DC power supply not to function properly 120Hz Bad filter capacitor 120Hz Defective diode in the DC power supply 60Hz Loose or corroded connector forming a diode junction 60Hz Hum Modulation Test Procedure Step 1 Tune to the carrier frequency or TV channel that you want to perform the test on if not already tuned The input attenuator can be set to view the carrier on screen however the AT 2000R RQ will auto range the attenuator while performing the test Press ESC if necessary to return to the top level of function key menus which display the HUM choices To tune while in the HUM mode press the blue FREQ key on the front panel At this point you can key in a channel number and press the ENTER key This is the default mode when choosing FREQ If you wish to key in a specific freque
95. specifications Without Preselector amp 77 Channel Loading Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 11 Digital Measurement QAM 64 256 Specifications Modulation Modulation Type 64 256 QAM DUS 031 ITU T J 83 Annex B Constellation Display Size 64 and 256 QAM Full constellation with zoom capability Adaptive Equalizer Display Number of Taps 8 feed forward 8 feedback Scale 10 to 40 dBc Mask DVB Digital Carrier Average Power Measurement Amplitude Range 30 to 35 dBmV or 30 to 60 dBmV with pre selector Resolution 0 1 dB Absolute Accuracy 1 5 dB Bandwidth Range 200 kHz to 200 MHz Adjacent Channel Power Difference Amplitude Range 10 to 25 dB ACCUTACY 2 1 dB Display Vertical Scale 20 to 40 dBmV 65 to 5 dBm Modulation Error Ratio MER Range
96. t of the screen includes F1 DEFAULT 1 and F2 DEFAULT 2 You can create 4 customised USER colour settings by pressing F3 USER 1 to F6 USER 4 Use the spin knob to select the desired item that you want to edit and use the arrow keys to select the desired colour for that item When all item colours have been chosen press ENTER 1 to save and exit the COLOR SETUP mode If you wish to exit without saving press ESC and a prompt will question Exit without save ENTER will exit the screen ESC will allow you to remain in COLOR SETUP mode until you are ready to save set up and exit Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 43 Channel Plan Set up The Channel Plan feature is only available with the optional CATV MEASUREMENT PAK A directory shows 4 separate channel plans that you can edit and customise Channel Plans are helpful when dealing with multiple CATV headends that have different channel line ups From the Channel Plan directory screen you can also edit the CHANNEL FREQUENCY allocation and NTSC PAL transmission standards Edit Plan The CHANNEL PLAN C Channel Plans 4 z Plan is used to select the Manager Position Type Test Channel Freq MHz TUSound MHz channels to be measured TT 1 2 TU Y 2 55 2566 4 5000 Switch during AUTOTEST 3 TU Y 3 61 2560 4 5000 Type mode and to permit 5 mw oY os 77 2509 4 5000 S 6 TU Y 6 83 2566 4 5000 setting frequency offsets 7 woe 1 175
97. t the multiburst frequencies press FS MULTI BURST SETUP and set each frequency of the burst These are the reference points for calculating the peak to peak frequency response in dB Depth of Modulation The video depth of modulation screen provides percent AAA modulation in both graphical and precise numeric format The depth of modulation is measured as the percentage of the total amplitude change of the carrier as the signal progresses from synch tip to peak white Standard video modulation requires sr 87 of the total range of the carrier envelope from full carrier to no carrier Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 66 Depth Of Modulation With VITS Accurate and repeatable measurement of depth of modulation requires a video test signal However good measurements may also be made on program material with a vertical interval test signal or VITS A test signal transmitted on the VITS of program video provides a standard to calibrate the video depth of modulation Press F4 LINE SELECT and select a VITS video line with white reference Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 67 QAM 64 256 Digital Measurement Analyzer Optional on AT 2000R Introduction to Digital Measurements As digital signals become more widespread performing accurate digital cable measurements is essential to efficiently install and maintain the cable network U
98. tails of how to add channels or frequencies After the AUTOTEST measurements the display can be scanned with the knob or arrow keys to view the measurements AUTOTEST measurements can be stored for later scanning or printing Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 55 Distortion Measurements Because of the nature of a broadband network and the cascading of RF amplifiers certain parameters of operation must be maintained to achieve optimum operation This optimum operation includes maximising the Carrier to Noise ratio the actual ratio of carrier level on the system to the system noise floor at any point in the system and maximising the Carrier to Intermodulation ratios The intermodulation ratios include both random intermodulation which could be noted on almost any active RF system and CATV specific intermodulation which includes unique types of intermodulation created during the transmission of CATV type carriers All software routines for measuring CATV distortions are designed for optimal performance and follow the NCTA Recommended Practices for Measurements on Cable Television Systems To further enhance distortion measurement capabilities the Model AT 2000R RQ has a built in pre amp thus achieving a 70 dB on screen dynamic measurement range with a sensitivity of 65 dBmV to 65 dBmV True level measurement accuracy is 0 75 dB including all internal system components such as attenuator flatn
99. tenuation for the measurement of the Analyzer noise floor NO If no filter used Step 3 Press the MEASURE F6 softkey to start the measurement During the test the AT 2000R RQ measures the peak amplitude of the carrier under test and the internal noise of the Analyzer and temporarily saves them The AT 2000R RQ will then prompt the user to turn off the test carrier or remove the modulation and then reduce the attenuation to obtain a beat measurement of at least 10 dB above the internal noise of the analyzer Step 4 Press ENTER I to confirm that all of the steps have been performed and the measurement will proceed The test results will be displayed at the bottom of the screen and will show the frequency where the measurement was taken the measured CSO ratio in dB and the Beat near Noise Correction factor used in the calculation It is recommended that measurements are made with as little noise near noise correction as possible CSO Gated in service Method This method does not require the removal of the RF carrier or modulation of the channel under test but sometimes under some circumstances is a slightly less accurate method Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 64 Step 1 Tune to the carrier frequency or TV channel Step 2 The input attenuator should be set so that the system noise is at least 10 dB above the internal noise of the analyzer The AT 2000R RQ will auto range the attenuat
100. tesse rersrorosse 40 KEE 40 ORIA AE STE LOLA ee EE 40 CUSTOMS ren EE 43 Ch nn bPlan Setup laa 44 USING AVANTRON S AT 2000R RQ SPECTRUM ANALYZER eessen 46 MAIN CONTROL KEYS amp MENUS niire iare sati aT aean T EIn EEEE ETE nE EIEE ETE E TEES ai 47 PPE QUENCY EE 47 Kr 48 Zero Span eeo r A A A A A acia 48 Resolution Bandwidth ORBWI nn nnnnnnnnnnnnnn nn nnnnnnnnnnnnnnnnnnnccnannonnns 49 Sweep LIMA E EE 49 Video Bandwidth VW 50 Amphi dE eebe e EE EE eiert 50 Sensitivity Measuring Low Level Signals ccccscccsssccesesssseesenecesseeeseecssceceseecesaeceseeecsaeecseesesaeeesaeeeseeesaaees 50 Mia EE 51 PRECISION FREQUENCY COUNTER EE 52 CATVPAK AUTOMATED CATV MEASUREMENTS OPTIONAL ccccccsssssssscccscssscscccscscccscccccssees 53 DIGITAL CHANNEL POWER eeneg genee e E 53 FREQUENCIES AND LEVELS ee okt EE ee ee ee EEN Ee See ias 54 TV CHANNEL Mode sx A ST EE O TO O AE 54 MultCarrie Mode xa A A IA RI a rs Ne ia OE SE E 54 BUTOTE EE 55 DISTORTION MEASUREMENTS bg ee EE AE ea ted dare 56 Hum Modulation Measurement A 6 SS A EE REE EE TE OE Lada 56 Combined C N NR CT Boiss A ts SDE AG EG EERE ta RG asd 58 LE TE EE 59 Composite ImplezBeat ClbBl a 62 Composite Second Order CSO 63 IN CHANNEL FREQUENCY RESPONSE 0sssccccccccsssssecccceesseusseeecccceeeeusseeeccccessauenseecccceesauanseeccceseeuanesceeeeeeesaannees 66 DEPTH OF MODULATION det raid 66 Depth Of Modulation With VITS a A at Eed 67 QAM 64 256 DIGITAL
101. the Video NTSC output Video NTSC Timer Set Video NTSC output off delay time in minutes Video NTSC on Boot On Off Set Video NTSC output in the ON position when unit starts up boots Display Switch Information On Off For use in remote control applications which use a testpoint switch controled by the AT 2000R RQ This option shows the information regarding the switch position live on screen Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 41 Company Identification Enter your company name in alphanumeric characters via the keypad Maximum 30 characters User Identification Enter your name in alphanumeric characters via the keypad Maximum 30 characters Date Format Toggle between International or US date and time format Depending on the selection of US or International settings the Temperature in the MAIN MENU screen will display in degrees Celsius INTERNATIONAL or Fahrenheit US Date Set current date on internal clock calendar MMDD Y Y Unit is year 2000 Y2K compliant Time Set current time on internal clock calendar HHMMSS Invalid Key Beep On Off A warning beep sounds when an invalid key is pressed if activated ON Power Off Beep On Off A warning beep sounds when the timer initiates the shutdown process if active This allows the user to ignore the warning and let the unit auto shut down or to intervene by pressing a key to restart the timer and continue operat
102. the top left of the screen the display shows the external Temperature in degrees Celsius or Fahrenheit depending on the selection of US or International settings in Date Time parameters The battery voltage is displayed at the top center of the screen The day date and time are displayed at the top right of the screen Temp 32 F Batt 8 9U Sep 17 1999 64 04 59 PH DIGITAL QAH CH POWER ANALYZER IN CHAN DEPTH OF FREQ MOD REMOTE INPUT Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 23 Standard Functions and Icons Spectrum Analyzer Full function 1 to 1 GHz Spectrum Analysis Freq Counter Allows the selected center frequency to be measured with better than 1kHz precision The Amplitude in dBmV is also displayed Setup Allows the user to upload either stored Records Database file or a choice of several other configuration files Channel Plans Colors etc to the Avantron Model AT 2000R RQ spectrum analyzers Remote Allows the user to download or retrieve either Records Database file or a choice of several other configuration files Channel Plans Colors etc from the Avantron Model AT 2000R RQ spectrum analyzers for storage on the PC Optional Functions and Icons System Sweep Used in conjunction with Avantron s Digital safe Low Level Non Interfering Sweep System provides the user with a true view of broadband frequency response SWP option BAS Activates internal BAS telemetry rece
103. ting problems by allowing the operator to identify the type of impairment and isolate the source Following installation and adjustment of modulators amplifiers and splitters modulation impairments can appear due to various I and Q vectors being distorted in amplitude or phase Zoom Mode The AT 2000RQ also includes a ZOOM mode feature Select F6 MORE 1 2 to get to the second menu level Press F4 ZOOM and a frame appears around 1 4 of the constellation Use the spin knob or arrow keys to move the frame to any one of the corners of the constellation and press Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 76 the ENTER key to select it for zooming QAM 64 has 1 level of zoom from 64 to 16 and QAM 256 mode has 2 levels of zoom 256 to 64 to 16 Pressing F5 GRID ON OFF allows turning the grid off and viewing the constellation with out the grid boundaries showing Statistics Graph Display The constellation analysis and the MER EVM ENM measurements are a convenient way to diagnose a system but quite often it is convenient to characterize a connection for a longer period of time The AT 2000RQ has the capability to gather and store statistics for a period of 1 to 60 minutes or 1 to 72 hours Error Statistics Recorded measurements are MER EVM ENM on graph form plus 4 events time markers for the following ES or ERRORRED SECOND that is within each measurement second if o
104. tion is if the spurious beats increase by 10 dB while only reducing the attenuator by 5 dB This 2 1 ratio is an indication that the input of the analyzer is overloading and causing excessive distortions Measuring with an overload condition will cause errors in the measurement results and can damage the input of the AT 2000R RQ The use of a pre selector filter is suggested in order to prevent the overloading of the analyzer and ensure precise repeatable tests With the Combined Distortion Tests function Carrier to Noise C N Composite Triple Beat CTB and Composite Second Order CSO are measured simultaneously reducing the number of times that the channel carrier is disabled Measure and store the whole routine as 1 record Measurements are semi automated IN CHANNEL type and require momentary disabling of channels carriers as well as user confirmation of specific steps during testing The procedure for performing this combined test is similar to any of the individual measurement modes Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 58 Carrier To Noise C N Television visual carrier to noise ratio is the power in a sinusoidal signal whose peak is equal to the peak of a visual carrier divided by the associated system noise power in a 4 MHz bandwidth This ratio is expressed in dB A critical parameter that is affected by the actual level of the carriers on the system is the catrier to noise ratio of the system
105. to the Channel Plans Menu Scroll through the displayed channels by using either the spin knob to highlight your choice on this page or use the arrow keys Pg Dn y Pg Up to access the other pages You are able to tag or untag the channels that are to be included in AUTO TEST by selecting Tag Untag AutoTest F3 Once your changes are made press the ENTER 4 key to save To edit a Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 44 frequency select from the on screen menu Edit Frequency FS make your changes and save The same procedures are followed to edit TV Sound and Edit Channel F1 PLAN MANAGER Returns you to the Channel Plan directory F2 Switch Type Switch channel type between TV FM or User Defined CW F3 Tag Untag AutoTest This switch TAG selects if the channel or frequency is included in the AUTOTEST mode F4 Edit Channel Allows entering an alpha numeric Channel identification F5 Edit Frequency Allows editing the frequency in MHz F6 Edit TV Sound Allows you to edit the intercarrier spacing of a TV channel in MHz Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 45 Using Avantron s AT 2000R RO Spectrum Analyzer Your new Model AT 2000R RQ Spectrum Analyzer is an invaluable tool for use in today s modern broadband network The field portable Spectrum Analyzer with it s broad spectrum input SMHz 1GHz excellent resolution se
106. ts are discovered notify your Avantron representative for instructions on how to proceed If the equipment has to be returned to an Authorised Avantron Service Center carefully repackage it in the original shipping container The original Avantron shipping container and packing materials should be saved for possible future use they are useful for long term storage and protecting the equipment if the analyzer must be moved long distances Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 16 Warranty Information AVANTRON products are warranted against defects in materials and workmanship for a period of 2 years from date of sale AVANTRON agrees to repair or replace any assembly or component found to be defective under normal use during this period The obligation under this warranty is limited solely to repairing the instrument which proves to be defective within the scope of the warranty when returned to the factory Transport costs to the factory is to be prepaid by the customer AVANTRON assumes no liability for secondary charges or consequential damages and in any event AVANTRON s liability for breach of contract shall not exceed the purchase price of the products shipped and against which a claim is made Any application recommendation made by AVANTRON for the use of its products are based upon tests believed to be reliable and accurate but AVANTRON makes no warranty for the results to be obtained This warr
107. ucts generated by the direct addition or subtraction of fundamental visual carrier frequencies CSO products normally fall at 750 kHz or 1 25 MHz from the visual carriers and require the removal of modulation for measurement In practice only the components above visual carrier are measured as they fall in the channel of interest During the test sequences the AT 2000R RQ will apply a correction factor for Beat Near Noise Correction The beat correction factor obtained when the internal noise of the spectrum analyzer is compared to the measured system noise in dB will be displayed separately at the bottom of the screen although the value is already added to the CTB measurement displayed Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 63 CSO In Channel Method Step 1 Tune to the carrier frequency or TV channel by one of the methods previously described The input attenuator can be set to view on screen the carrier being measured however the AT 2000R RQ will auto range the attenuator when measuring the carrier level Press ESC if necessary to return to the top level of function key menus which displays the choices Step 2 With the softkey menu select the following combination F1 gt SINGLE F2 gt CSO F3 gt IN CH F4 PRE FILTER gt YES Recommended to prevent overloading the analyzer user supplied equipment and installed at the input of AT 2000R RQ allows for the reduction of at
108. w keys Pg Up sw SUP MAIN OUTPUT TP v SW SWP BRIDGER OUTPUT SER A T SS Pg Dn J to access SW SWP HIGH RES REF AT N 10 19 97 08 records on the other pages Tag the highlighted record by selecting from the on screen menu Tag Item F3 key If you wish to delete all records from memory select from the on screen menu Tag All Items F4 A prompt will question you Do You Wish to Delete All Tagged Records Press ENTER to continue or ESC to cancel the operation A second prompt will confirm that All Tagged Records Will Be Permanently Deleted Continue you now have one last chance to press ESC to cancel operation or ENTER will continue and delete tagged items Printing Reports And Screens Documenting CATV proof of performance testing using the Model AT 2000R RQ The AT 2000R RQ supports 2 printer drivers a standard EPSON compatible which works well with most types of dot matrix and ink jet printers The second driver is for laser printers emulating the Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 30 HP Laser standard For printer selection see section 4 2 User Parameters Printer Type Epson HP Connecting the AT 2000R RQ to a compatible printer is simple Simply connect a printer cable to the 25 pin connector port which is located on front panel behind the drop down door and the printer Some printers may not function properly Print Screen Method Thi
109. y Reference AgZiNg 1 PPM Yr Temperature Stability 1 PPM 0 C to 50 C Frequency counter CCUTACY 1 PPM 1count Resolution 10 Hz Stability Noise sidebands offset from CW signal 85 dBc 10kHz SPAN Frequency Span Range Variable from Max Span 1000 MHz to 100 kHz amp Zero Span ACCULACY nr lt 2 PPM Sweep Time Ran ge 3mS 6mS 15ms 30mS 100mS 300mS 1000mS 3000mS Stability lt 2 PPM Sweep Trigger Automatic Sweep Mode only Free Run Linelock and TV Frame Resolution Bandwidth Range 1 MHz 300 kHz 30 kHz amp 10 kHz CCUTACY 5 Selectivity 60 dB 3dB Ratio 5 3 1 3 1 2 1 2 1 Video Bandwidth Range 1 MHz 100 kHz amp 10 kHz Avantron AT 2000R RQ Spectrum Analyzer User Manual 4 0 preliminary 8 AMPLITUDE Response Flatness

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